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POLIME VÀ VẬT LIỆU POLIME

Loại tơ nào sau đây được điều chế bằng phản ứng trùng hợp?

Hóa học Lớp 11

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2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Khi thủy phân hoàn toàn một tripeptit mạch hở X thu được hỗn hợp sản phẩm gồm alanin và glyxin. Số công thức cấu tạo của X thỏa mãn là

Hóa học Lớp 12

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions. Parents’ choice (A) for their (B) children’s names are based (C) on names of their relatives (D) or ancestors.

Tiếng Anh Tốt nghiệp THPT

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Bài 8: Điện năng. Công suất điện.

Biết hiệu điện thế giữa hai đầu dây dẫn là 6V. Điện năng tiêu thụ trên dây dẫn khi có dòng điện cường 2A chạy qua trong 1 giờ là

Vật lý Lớp 11

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POLIME VÀ VẬT LIỆU POLIME

Tơ nilon – 6,6 là:

Hóa học Lớp 11

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Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 14)

Cho các chất: saccarozơ, glucozơ, fructozơ, etyl fomat, axit fomic và anđehit axetic.Trong các chất trên, số chất vừa có khả năng tham gia phản ứng tráng bạc vừa có khả năng với Cu(OH)2 ở điều kiện thường là

Hóa học Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions. Factories located (A) on the coastlines have (B) released untreated pollution (C) directly (D) into the ocean.

Tiếng Anh Tốt nghiệp THPT

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future, many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenDoctors have tentatively concluded that cell phones may

Tiếng Anh Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions. It is the job interview (A) that you should be (B) prepared to mention (C) a salary range (D).

Tiếng Anh Tốt nghiệp THPT

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BỘ ĐỀ THI THPT QUỐC GIA CHUẨN CẤU TRÚC BỘ GIÁO DỤC MÔN TIẾNG ANH (P2)

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questionsYou have to be on your toes if you want to beat her

Tiếng Anh Tốt nghiệp THPT

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Chương IV. CÁC ĐỊNH LUẬT BẢO TOÀN (P2)

Một vật có khối lượng 0,5 kg trượt không ma sát trên một mặt phẳng ngang với tốc độ 5 m/s đến đập vào một bức tường thẳng đứng theo phương vuông góc với tường. Sau va chạm vật bật ngược trở lại phương cũ với tốc độ 2 m/s. Thời gian tương tác là 0,2 s. Lực F→ do tường tác dụng lên vật có độ lớn bằng

Vật lý Lớp 10

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Bài tập hình học không gian Oxyz từ đề thi Đại học cực hay có lời giải (P2)

Trong không gian Oxyz, một vectơ pháp tuyến của mặt phẳng x-2+y-1+z3=1 là

Toán Lớp 12

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Bài 8: Điện năng. Công suất điện.

Hai bóng đèn có công suất lần lượt là: P1 và P2 với P1 < P2đều làm việc bình thường ở hiệu điện thế U. Cường độ dòng điện qua mỗi bóng đèn và điện trở của mỗi bóng đèn có mối liên hệ:

Vật lý Lớp 11

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Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 14)

Thủy phân hoàn toàn 8,68 gam tetrapeptit mạch hở X (được tạo nên từ ba α-amino axit có công thức dạng H2NCnH2nCOOH) bằng dung dịch NaOH dư, thu được 14,36 gam muối. Mặt khác thủy phân hoàn toàn 8,68 gam X bằng dung dịch HCl dư, thu được m gam muối. Giá trị của m là

Hóa học Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.Not many students get high scores today. The tests are to hard.

Tiếng Anh Tốt nghiệp THPT

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Bài tập về Este - Lipit cực hay có lời giải chi tiết (P11)

X,Y là hai hữu cơ axit mạch hở ( MX < MY ). Z là ancol no, T là este hai chức mạch hở không nhánh tạo bởi X, T, Z. Đun 38,86 gam hỗn hợp E chứa X, Y, Z, T với 400ml dung dịch NaOH 1M vừa đủ thu được ancol Z và hỗn hợp F chứa hai muối có số mol bằng nhau. Cho Z vào bình chứa Na dư thấy bình tăng 19,24 gam và thu được 5,824 lít H2 ở đktc. Đốt hoàn toàn hỗn hợp F cần 15,68 lít O2 (đktc) thu được khí CO2, Na2CO3 và 7,2 gam H2O. Phần trăm số mol của T trong E gần nhất với:

Hóa học Lớp 12

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BỘ ĐỀ THI THPT QUỐC GIA CHUẨN CẤU TRÚC BỘ GIÁO DỤC MÔN TIẾNG ANH (P2)

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions It was relatively easy for him to learn baseball because he had been a cricket player.

Tiếng Anh Tốt nghiệp THPT

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future, many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe changes possibly caused by the cell phones are mainly concerned with ______.

Tiếng Anh Tốt nghiệp THPT

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Đề thi thử THPT Quốc Gia năm 2019 môn Vật Lý (Đề số 1)

Theo thuyết lượng tử ánh sáng thì năng lượng của

Vật lý Tốt nghiệp THPT

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2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Giả sử pentapeptit (X) mạch hở khi thủy phân không hoàn toàn chỉ thu được Val-Ala, Gly-Gly, Ala-Gly-Gly, Gly-Val. Số chất (X) thỏa mãn điều kiện trên là

Hóa học Lớp 12

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ĐỀ 11

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.They travelled to the capital city of Scotland by the most ____________ route.

Tiếng Anh Tốt nghiệp THPT

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Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions below.Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show w hy speech is primary and writing secondary to language. Human beings have been writing (as far as we can tell from surviving evidence) for at least 5000 years; but they have been talking for much longer, doubtless ever since there have been human beings.When writing did develop, it was derived from and represented speech, although imperfectly. Even today there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any human child who is not severely handicapped physically or mentally will learn to talk: a normal human being cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write. In the past many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write, while some who learn the rudiments of those skills do so only imperfectly.To affirm the primacy of speech over writing is not, however, to disparage the latter. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.The word “advantage” in the last paragraph most closely means ______.

Tiếng Anh Tốt nghiệp THPT

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Tổng hợp đề thi Tiếng Anh có lời giải (Đề số 17)

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 35 to 44.Here are tips that help succeed in your job interview:Always arrive early. If you do not know (35) the organization is located, call for exact directions (36) advance. Leave some extra time for any traffic, parking, or (37) events. If you are running late, call right away and let someone know. The best time to arrive is approximately 5 - 10 minutes early. Give (38) the time to read your resume one more time, to catch your breath, and to be ready for the interview. Once you are at the office, treat everyone you encounter with respect. Be (39) to everyone as soon as you walk in the door.Wear a professional business suit. This point should be emphasized enough. First (40) are extremely important in the interview process. Women should (41) wearing too much jewelry or make up. Men should avoid flashy suits or wearing too much perfume. It is (42) important that you feel comfortable. While a suit is the standard interview attire in a business environment, if you think it is (43) informal environment, call before and ask. Regardless, you can never be overdressed (44) you are wearing a tailored suit.Question 42

Tiếng Anh Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questionsGreenpeace has realized the seriousness of environmental pollution. It urges the government worldwide to take action soon.

Tiếng Anh Tốt nghiệp THPT

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future, many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe man mentioned in the passage, who used his cell phone too often, ______.

Tiếng Anh Tốt nghiệp THPT

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BỘ ĐỀ THI THPT QUỐC GIA CHUẨN CẤU TRÚC BỘ GIÁO DỤC MÔN TIẾNG ANH (P2)

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.With the final examinations coming very soon his anxiety was rising to almost unbearable limits

Tiếng Anh Tốt nghiệp THPT

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Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 14)

Este X đơn chức tác dụng với NaOH đun nóng thu được muối Y có công thức phân tử là C3H3O2Na và ancol Y1. Oxi hóa Y1 bằng CuO dư nung nóng chỉ thu được anđehit Y2. Cho Y2 tác dụng với lượng dư AgNO3 trong dung dịch NH3, đun nóng thu được số mol Ag gấp 4 lần số mol Cu được tạo thành trong thí nghiệm oxi hóa ancol. Chất X là

Hóa học Tốt nghiệp THPT

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ĐỀ 11

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.Make sure you end each sentence with a ___________

Tiếng Anh Tốt nghiệp THPT

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future, many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenAccording to the passage, what makes mobile phones potentially harmful is ______.

Tiếng Anh Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions. She couldn’t believe when he told her his age. He looked so young but he was a good ten years older than her.

Tiếng Anh Tốt nghiệp THPT

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Tổng hợp đề thi thử THPTQG môn Vật Lí cực hay có lời giải (Đề số 1)

Hai dao động điều hòa cùng phương, cùng tần số, ngược pha nhau có biên độ lần lượt là A1 và A=2. Dao động tổng hợp của hai động này có biên độ là

Vật lý Tốt nghiệp THPT

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BỘ ĐỀ THI THPT QUỐC GIA CHUẨN CẤU TRÚC BỘ GIÁO DỤC MÔN TIẾNG ANH (P2)

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.It was necessary to divide the movie “Roots” into five parts in order to show it on television

Tiếng Anh Tốt nghiệp THPT

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Chương IV. CÁC ĐỊNH LUẬT BẢO TOÀN (P2)

Một chất điểm có khối lượng m bắt đầu trượt không ma sát từ trên mặt phẳng nghiêng xuống. Gọi α là góc của mặt phẳng nghiêng so với mặt phẳng nằm ngang. Động lượng của chất điểm ở thời điểm t có độ lớn là

Vật lý Lớp 10

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2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Khi thủy phân hết pentapeptit X (Gly–Ala–Val–Ala–Gly) thì thu được tối đa bao nhiêu sản phẩm chứa gốc glixyl mà dung dịch của nó có phản ứng màu biure?

Hóa học Lớp 12

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future, many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenAccording to the writer, people should ______.

Tiếng Anh Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions. I think we should tell Peter that the location of the picnic has been changed. Let’s put him in the picture.

Tiếng Anh Tốt nghiệp THPT

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Đề thi thử THPTGQ môn Toán cực cực hay có lời giải chi tiết(Đề 2)

Tính tích phân ∫020187xdx

Toán Tốt nghiệp THPT

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future, many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe word “potentially” in the passage most closely means ______.

Tiếng Anh Tốt nghiệp THPT

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BỘ ĐỀ THI THPT QUỐC GIA CHUẨN CẤU TRÚC BỘ GIÁO DỤC MÔN TIẾNG ANH (P2)

Mark the letter A, B, C, or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges - John : “What kind of job would you like?- Tim : “___________”.

Tiếng Anh Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35. The fictitious androids written about in the mid-1900s are becoming a reality with advances in the field of robotics. Japan and Korea have been pioneers in this field. They regularly compete to be the first. The focus on most reseachers is in (31) life-like, attractive female androids. A Japanese research group led by Hiroshi Ishiguro created ther world’s first female android, which is called Actroid in 2003. The early model was limited so upgrades were made and the dramatic entertainment model was released in 2006. Actroids are covered with a silicone skin and have built-in sensors making them (32) of reacting to humans, and they can also mimic many human behaviors. (33) , they can be programmed to speak in any language. The Korean android, EveR-2, released in 2006, was designed by a team from Kitech. They claim that she is more life-like than Actroids, and she can mimic emtions. She can also speak and move her lips to match her (34) . Future models are expected to have higher mobility and even be proficient in dancing. Research teams have also created male androids. One in particular is the Germinoid HI-I.Regardless of the competition, it’s clear that this technology will one day present us (35) the dilemma of determining human from machine.Điền ô số 35

Tiếng Anh Tốt nghiệp THPT

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future, many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe phrase “negative publicity” in the passage most likely means______.

Tiếng Anh Tốt nghiệp THPT

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2.5. Xác định cấu tạo peptit qua phản ứng thủy phân

Khi thủy phân không hoàn toàn pentapeptit Ala-Gly-Val-Gly-Ala được tối đa bao nhiêu tripeptit khác nhau?

Hóa học Lớp 12

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ĐỀ 11

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.She loves London, ____________ in the spring.

Tiếng Anh Tốt nghiệp THPT

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BỘ ĐỀ THI THPT QUỐC GIA CHUẨN CẤU TRÚC BỘ GIÁO DỤC MÔN TIẾNG ANH (P2)

Mark the letter A, B, C, or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges - David: “Do you fancy going to a movie this evening?”- Lisa: “ ___________ ”

Tiếng Anh Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35. The fictitious androids written about in the mid-1900s are becoming a reality with advances in the field of robotics. Japan and Korea have been pioneers in this field. They regularly compete to be the first. The focus on most reseachers is in (31) life-like, attractive female androids. A Japanese research group led by Hiroshi Ishiguro created ther world’s first female android, which is called Actroid in 2003. The early model was limited so upgrades were made and the dramatic entertainment model was released in 2006. Actroids are covered with a silicone skin and have built-in sensors making them (32) of reacting to humans, and they can also mimic many human behaviors. (33) , they can be programmed to speak in any language. The Korean android, EveR-2, released in 2006, was designed by a team from Kitech. They claim that she is more life-like than Actroids, and she can mimic emtions. She can also speak and move her lips to match her (34) . Future models are expected to have higher mobility and even be proficient in dancing. Research teams have also created male androids. One in particular is the Germinoid HI-I.Regardless of the competition, it’s clear that this technology will one day present us (35) the dilemma of determining human from machine.Điền ô số 34

Tiếng Anh Tốt nghiệp THPT

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20 Đề ôn thi Tiếng Anh chuẩn cấu trúc có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future, many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health. On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenAccording to the passage, cell phones are especially popular with young people because ______.

Tiếng Anh Tốt nghiệp THPT

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Tổng hợp đề thi thử THPT quốc gia môn tiếng anh có lời giải chi tiết (Đề số 19)

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions below.Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show w hy speech is primary and writing secondary to language. Human beings have been writing (as far as we can tell from surviving evidence) for at least 5000 years; but they have been talking for much longer, doubtless ever since there have been human beings.When writing did develop, it was derived from and represented speech, although imperfectly. Even today there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any human child who is not severely handicapped physically or mentally will learn to talk: a normal human being cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write. In the past many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write, while some who learn the rudiments of those skills do so only imperfectly.To affirm the primacy of speech over writing is not, however, to disparage the latter. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized.In the author’s judgment, ______.

Tiếng Anh Tốt nghiệp THPT

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ĐỀ THI THỬ THPT QUỐC GIA NĂM 2019 – LẦN 2 Môn thi: TIẾNG ANH (Đề 11)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35. The fictitious androids written about in the mid-1900s are becoming a reality with advances in the field of robotics. Japan and Korea have been pioneers in this field. They regularly compete to be the first. The focus on most reseachers is in (31) life-like, attractive female androids. A Japanese research group led by Hiroshi Ishiguro created ther world’s first female android, which is called Actroid in 2003. The early model was limited so upgrades were made and the dramatic entertainment model was released in 2006. Actroids are covered with a silicone skin and have built-in sensors making them (32) of reacting to humans, and they can also mimic many human behaviors. (33) , they can be programmed to speak in any language. The Korean android, EveR-2, released in 2006, was designed by a team from Kitech. They claim that she is more life-like than Actroids, and she can mimic emtions. She can also speak and move her lips to match her (34) . Future models are expected to have higher mobility and even be proficient in dancing. Research teams have also created male androids. One in particular is the Germinoid HI-I.Regardless of the competition, it’s clear that this technology will one day present us (35) the dilemma of determining human from machine. Điền ô số 33

Tiếng Anh Tốt nghiệp THPT

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Bộ đề luyện thi THPTQG Hóa Học cực hay có lời giải chi tiết (Đề số 14)

Có một số hợp chất sau: (1) etilen, (2) vinyl clorua, (3) axit adipic, (4) phenol, (5) acrilonitrin, (6) buta-1,3-dien. Những chất tham gia phản ứng trùng hợp là

Hóa học Tốt nghiệp THPT

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Đề thi thử THPT Quốc Gia năm 2019 môn Vật Lý (Đề số 1)

Chiếu tới bề mặt của một kim loại bức xạ có bước sóng l, giới hạn quang điện của kim loại đó là λ0. Biết hằng số Plăng là h, vận tốc ánh sáng trong chân không là c. Để có hiện tượng quang điện xảy ra thì

Vật lý Tốt nghiệp THPT

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Lớp 12

Lớp 11

Lớp 10

Ôn vào 10

Lớp 9

Lớp 8

Lớp 7

Lớp 6

Ôn vào 6

Lớp 5

Lớp 4

Lớp 3

Lớp 2

Lớp 1

Đại học

ĐGNL - ĐGTD

Tốt nghiệp THPT

Ôn vào 10

Ôn vào 6

V-ACT

Toán

Văn

Tiếng Anh

Vật lý

Hóa học

Sinh học

Lịch sử

Địa lý

Giáo dục Kinh tế và Pháp luật

Tin học

Công nghệ

Toán

Toán

Toán

Toán

Văn

Tiếng Anh

Vật lý

Hóa học

Sinh học

Khoa học tự nhiên

Tin học

Lịch sử

Địa lí

Toán

Toán

Toán

Toán

Tiếng Việt

Tiếng Anh

Danh sách câu hỏi ( Có 2,502,934 câu hỏi trên 50,059 trang )

Loại tơ nào sau đây được điều chế bằng phản ứng trùng hợp?

Khi thủy phân hoàn toàn một tripeptit mạch hở X thu được hỗn hợp sản phẩm gồm alanin và glyxin. Số công thức cấu tạo của X thỏa mãn là

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions. Parents’ choice (A) for their (B) children’s names are based (C) on names of their relatives (D) or ancestors.

Biết hiệu điện thế giữa hai đầu dây dẫn là 6V. Điện năng tiêu thụ trên dây dẫn khi có dòng điện cường 2A chạy qua trong 1 giờ là

Tơ nilon – 6,6 là:

Cho các chất: saccarozơ, glucozơ, fructozơ, etyl fomat, axit fomic và anđehit axetic.Trong các chất trên, số chất vừa có khả năng tham gia phản ứng tráng bạc vừa có khả năng với Cu(OH)2 ở điều kiện thường là

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions. Factories located (A) on the coastlines have (B) released untreated pollution (C) directly (D) into the ocean.

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions. It is the job interview (A) that you should be (B) prepared to mention (C) a salary range (D).

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questionsYou have to be on your toes if you want to beat her

Trong không gian Oxyz, một vectơ pháp tuyến của mặt phẳng x-2+y-1+z3=1 là

Hai bóng đèn có công suất lần lượt là: P1 và P2 với P1 < P2đều làm việc bình thường ở hiệu điện thế U. Cường độ dòng điện qua mỗi bóng đèn và điện trở của mỗi bóng đèn có mối liên hệ:

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.Not many students get high scores today. The tests are to hard.

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions It was relatively easy for him to learn baseball because he had been a cricket player.

Theo thuyết lượng tử ánh sáng thì năng lượng của

Giả sử pentapeptit (X) mạch hở khi thủy phân không hoàn toàn chỉ thu được Val-Ala, Gly-Gly, Ala-Gly-Gly, Gly-Val. Số chất (X) thỏa mãn điều kiện trên là

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.They travelled to the capital city of Scotland by the most ____________ route.

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questionsGreenpeace has realized the seriousness of environmental pollution. It urges the government worldwide to take action soon.

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.With the final examinations coming very soon his anxiety was rising to almost unbearable limits

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.Make sure you end each sentence with a ___________

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions. She couldn’t believe when he told her his age. He looked so young but he was a good ten years older than her.

Hai dao động điều hòa cùng phương, cùng tần số, ngược pha nhau có biên độ lần lượt là A1 và A=2. Dao động tổng hợp của hai động này có biên độ là

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions.It was necessary to divide the movie “Roots” into five parts in order to show it on television

Khi thủy phân hết pentapeptit X (Gly–Ala–Val–Ala–Gly) thì thu được tối đa bao nhiêu sản phẩm chứa gốc glixyl mà dung dịch của nó có phản ứng màu biure?

Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions. I think we should tell Peter that the location of the picnic has been changed. Let’s put him in the picture.

Tính tích phân ∫020187xdx

Mark the letter A, B, C, or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges - John : “What kind of job would you like?- Tim : “___________”.

Khi thủy phân không hoàn toàn pentapeptit Ala-Gly-Val-Gly-Ala được tối đa bao nhiêu tripeptit khác nhau?

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.She loves London, ____________ in the spring.

Mark the letter A, B, C, or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges - David: “Do you fancy going to a movie this evening?”- Lisa: “ ___________ ”