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30 đề thi thử thpt quốc gia tiếng anh năm 2020 cực hay 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 answer to each of the questions from 28 to 34.Rain pounded down on the roof. I was trying to read but the sound was too loud. I couldn’t help myself from being a little grumpy. I wanted to be outside playing, but the rain was keeping me inside.My mom had gone to the grocery store, and my dad was spending Saturday at the office. I had planned to spend the day hiking, but Mother Nature decided that today was the perfect day for rain.It meant that I would have to entertain myself. I spent most of the morning playing with my stuffed animals and reading. I was sitting next to the window staring out when I got a strange idea: why not just go outside anyway?I put on my boots and a big raincoat and stepped out into the wet world. It was raining hard but it wasn’t cold. All I could hear were raindrops and the wind. I decided to go on my hike anyway.My feet didn’t make any sound on the wet ground and the forest seemed different. I went to my favourite place and sat down. In the summer, my best friend Ellen and I would come here and sit for hours. It was our special place. All of a sudden, I thought I heard someone shouting my name. I turned and saw Ellen walking up behind me.“Oh my Gosh! It’s really you, Martha!” she said. “I can’t believe that you are out here right now. I thought I would be the only person crazy enough to go for a walk in the rain.”I was very happy to have some company. We decided that hiking in the rain was just as fun as hiking in the sunshine. We planned on hiking in the rain again.Question:What did Martha think about being outside?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 472 lượt xem 6 năm trước
Bài 2: Phương trình lượng giác cơ bản

Giải phương trình sau: sin(x + 45o) = - √2/2

Toán Lớp 11
Xem chi tiết 28.8 K lượt xem 2 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Giải các phương trình:5x2-3x+1=2x+11

Toán Lớp 9
Xem chi tiết 5.7 K lượt xem 2 năm trước
Tổng hợp đề ôn tập thi THPTQG môn Sinh Học có đáp án (Đề số 16)

Cho các thông tin về diễn thế sinh thái như sau:(1) Xuất hiện ở môi trường đã có một quần xã sinh vật từng sống.(2) Có sự biến đổi tuần tự của quần xã qua các giai đoạn tương ứng với sự biến đổi của môi trường.(3) Song song với quá trình biến đổi quần xã trong diễn thế là quá trình biến đổi về các điều kiện tự nhiên của môi trường.(4) Luôn dẫn tới quần xã bị suy thoái.Các thông tin phản ánh sự giống nhau giữa diễn thế nguyên sinh và diễn thế thứ sinh là:

Sinh học Tốt nghiệp THPT
Xem chi tiết 282 lượt xem 6 năm trước
BÀI TẬP VỀ PHẢN ỨNG ESTE HÓA

Cho 37,6 gam hỗn hợp X gồm C2H5OH và một rượu đồng đẳng Y tác dụng với Na dư thu được 11,2 lít khí H2 ( đktc). Nếu cho Y bằng lượng Y có trong X tác dụng hết với axit axetic thì thu được số gam este là: 

Hóa học Lớp 12
Xem chi tiết 2.2 K lượt xem 6 năm trước
Bài 2: Phương trình lượng giác cơ bản

Giải phương trình sau: sinx = 1/3

Toán Lớp 11
Xem chi tiết 40.4 K lượt xem 2 năm trước
Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

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 .Why is it that flying to New York from London will leave you feeling less tired than flying to London from New York? The answer may be a clear case of biology not being able to keep up with technology. Deep inside the brain there is a “clock” that governs every aspect of the body’s functioning: sleep and wake cycles, levels of alertness, performance, mood, hormone levels, digestion, body temperature and so on. It regulates all of these functions on a 24-hour basis and is called the circadian clock (from the Latin, circa “about” + dies “day”).This body clock programmes us to be sleepy twice a day, between 3-5 a.m and again between 3-5 p.m. Afternoon tea and siesta times are all cultural responses to our natural biological sleepiness in the afternoon. One of the major causes of the travelers’ malady known as jet lag is the non-alignment of a person’s internal body clock with clocks in the external world. Crossing different time zones confuses the circadian clock, which then has to adjust to the new time and patterns of light and activity. To make matters more complex, not all internal body functions adjust at the same rate. So your sleep/wake may adjust to a new time zone at one rate, while your temperature adjusts at a different pace. Your digestion may be on a different schedule altogether.Though we live in a 24-hour day, the natural tendency of the body clock is to extend our day beyond 24 hours. It is contrary to our biological programming to shrink our day. That is why travelling in a westward direction is more body-clock friendly than flying east. NASA studies of long haul pilots showed that westward travel was associated with significantly better sleep quantity and quality than eastward flights. When flying west, you are “extending” your day, thus travelling in the natural direction of your internal clock. Flying eastward will involve “shrinking” or reducing your day and is in direct opposition to your internal clock’s natural tendency.One of the more common complaints of travelers is that their sleep becomes disrupted. There are many reasons for this: Changing time zones and schedules, changing light and activity levels, trying to sleep when your body clock is programmed to be awake, disruption of the internal circadian clock and working longer hours. Sleep loss, jet lag and fatigue can seriously affect our ability to function well. Judgment and decision-making can be reduced by 50%, attention by 75 percent, memory by 20 percent and communication by 30 percent. It is often suggested that you adjust your watch as soon as you board a plane, supposedly to try to help you adjust to your destination’s schedule as soon as you arrive. But it can take the body clock several days to several weeks to fully adjust to a new time zone.Jet lag _________

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.7 K lượt xem 6 năm trước
Bài 2: Phương trình lượng giác cơ bản

Có giá trị nào của x thỏa mãn phương trình sinx = -2 không?

Toán Lớp 11
Xem chi tiết 4 K lượt xem 2 năm trước
30 đề thi thử thpt quốc gia tiếng anh năm 2020 cực hay 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 answer to each of the questions from 28 to 34.Rain pounded down on the roof. I was trying to read but the sound was too loud. I couldn’t help myself from being a little grumpy. I wanted to be outside playing, but the rain was keeping me inside.My mom had gone to the grocery store, and my dad was spending Saturday at the office. I had planned to spend the day hiking, but Mother Nature decided that today was the perfect day for rain.It meant that I would have to entertain myself. I spent most of the morning playing with my stuffed animals and reading. I was sitting next to the window staring out when I got a strange idea: why not just go outside anyway?I put on my boots and a big raincoat and stepped out into the wet world. It was raining hard but it wasn’t cold. All I could hear were raindrops and the wind. I decided to go on my hike anyway.My feet didn’t make any sound on the wet ground and the forest seemed different. I went to my favourite place and sat down. In the summer, my best friend Ellen and I would come here and sit for hours. It was our special place. All of a sudden, I thought I heard someone shouting my name. I turned and saw Ellen walking up behind me.“Oh my Gosh! It’s really you, Martha!” she said. “I can’t believe that you are out here right now. I thought I would be the only person crazy enough to go for a walk in the rain.”I was very happy to have some company. We decided that hiking in the rain was just as fun as hiking in the sunshine. We planned on hiking in the rain again.Question:The word “company” in the last paragraph is closest in meaning to

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 425 lượt xem 6 năm trước
BÀI TẬP VỀ PHẢN ỨNG ESTE HÓA

Trộn 300 ml dung dịch axit axetic 1M và 50 ml ancol etylic 46º (d = 0,8 g/ml) có thêm một ít H2SO4 đặc vào một bình cầu và đun nóng bình cầu một thời gian, sau đó chứng cất thu được 19,8 g este. Hiệu suất của phản ứng este hóa là: 

Hóa học Lớp 12
Xem chi tiết 5 K lượt xem 6 năm trước
Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

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 .Why is it that flying to New York from London will leave you feeling less tired than flying to London from New York? The answer may be a clear case of biology not being able to keep up with technology. Deep inside the brain there is a “clock” that governs every aspect of the body’s functioning: sleep and wake cycles, levels of alertness, performance, mood, hormone levels, digestion, body temperature and so on. It regulates all of these functions on a 24-hour basis and is called the circadian clock (from the Latin, circa “about” + dies “day”).This body clock programmes us to be sleepy twice a day, between 3-5 a.m and again between 3-5 p.m. Afternoon tea and siesta times are all cultural responses to our natural biological sleepiness in the afternoon. One of the major causes of the travelers’ malady known as jet lag is the non-alignment of a person’s internal body clock with clocks in the external world. Crossing different time zones confuses the circadian clock, which then has to adjust to the new time and patterns of light and activity. To make matters more complex, not all internal body functions adjust at the same rate. So your sleep/wake may adjust to a new time zone at one rate, while your temperature adjusts at a different pace. Your digestion may be on a different schedule altogether.Though we live in a 24-hour day, the natural tendency of the body clock is to extend our day beyond 24 hours. It is contrary to our biological programming to shrink our day. That is why travelling in a westward direction is more body-clock friendly than flying east. NASA studies of long haul pilots showed that westward travel was associated with significantly better sleep quantity and quality than eastward flights. When flying west, you are “extending” your day, thus travelling in the natural direction of your internal clock. Flying eastward will involve “shrinking” or reducing your day and is in direct opposition to your internal clock’s natural tendency.One of the more common complaints of travelers is that their sleep becomes disrupted. There are many reasons for this: Changing time zones and schedules, changing light and activity levels, trying to sleep when your body clock is programmed to be awake, disruption of the internal circadian clock and working longer hours. Sleep loss, jet lag and fatigue can seriously affect our ability to function well. Judgment and decision-making can be reduced by 50%, attention by 75 percent, memory by 20 percent and communication by 30 percent. It is often suggested that you adjust your watch as soon as you board a plane, supposedly to try to help you adjust to your destination’s schedule as soon as you arrive. But it can take the body clock several days to several weeks to fully adjust to a new time zone.The word “It” refers to_________

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 0.9 K lượt xem 6 năm trước
Bài 2: Phương trình lượng giác cơ bản

Tìm một giá trị của x sao cho 2sinx – 1 = 0.

Toán Lớp 11
Xem chi tiết 839 lượt xem 6 năm trước
Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 10)

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 from 20 to 25.FIRST TIME IN THE AIRWhen John Mills was going to fly in an aeroplane for the first time, he was frightened. He did not like the idea of being thousands of feet up in the air. “ I also didn't like the fact that I wouldn't be in control,” says John.“I'm a terrible passenger in the car. When somebody else is driving, I tell them what to so. It drives everybody crazy.”However John couldn't avoid flying any longer. It was the only way he could visit his grandchildren in Canada. “I had made up my mind that I was going to do it, I couldn't let my son, his wife and their three children travel all the way here to visit me. It would be so expensive for them and I know Tom's business isn't doing so well at the moment – it would also be tiring for the children – it's a nine-hour flight!” he says.To get ready for the flight John did lots of reading about aeroplanes. When he booked his seat, he was told that he would be flying on a Boeing 747, which is better known as a jumbo jet. “I needed to know as much as possible before getting in that plane. I suppose it was a way of making myself feel better. The Boeing 747 is the largest passenger aircraft in the world at the moment. The first one flew on February 9th 1969 in the USA. It can carry up to 524 passengers and 3.400 pieces of luggage. The fuel for aeroplanes is kept in the wings and the 747 is wings are so big that they can carry enough fuel for an average car to be able to travel 16,000 kilometres a year for 70 years. Isn't that unbelievable? Even though I had discovered all this very interesting information about the jumbo, when I saw it for the first time, just before I was going to travel to Canada, I still couldn't believe that something so enormous was going to get up in the air and fly. I was even more impressed when I saw how big itwas inside with hundreds of people!”The biggest surprise of all for John was the flight itself. “The take-off itself was much smoother than I expected although I was still quite scared until we were in the air. In the end, I managed to relax, enjoy the food and watch one of the movies and the view from the window was spectacular. I even managed to sleep for a while! Of course,” continues John, “the best reward of all was when I arrived in Canada and saw my son and his family, particularly my beautiful grandchildren. Suddenly, I felt so silly about all the years when I couldn't even think of getting on a plane. I had let my fear of living stop me from seeing the people I love most in the world. I can visit my son and family as often as I like now!”Why did John Mills fly in an aeroplane?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1.7 K lượt xem 6 năm trước
Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

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 .Why is it that flying to New York from London will leave you feeling less tired than flying to London from New York? The answer may be a clear case of biology not being able to keep up with technology. Deep inside the brain there is a “clock” that governs every aspect of the body’s functioning: sleep and wake cycles, levels of alertness, performance, mood, hormone levels, digestion, body temperature and so on. It regulates all of these functions on a 24-hour basis and is called the circadian clock (from the Latin, circa “about” + dies “day”).This body clock programmes us to be sleepy twice a day, between 3-5 a.m and again between 3-5 p.m. Afternoon tea and siesta times are all cultural responses to our natural biological sleepiness in the afternoon. One of the major causes of the travelers’ malady known as jet lag is the non-alignment of a person’s internal body clock with clocks in the external world. Crossing different time zones confuses the circadian clock, which then has to adjust to the new time and patterns of light and activity. To make matters more complex, not all internal body functions adjust at the same rate. So your sleep/wake may adjust to a new time zone at one rate, while your temperature adjusts at a different pace. Your digestion may be on a different schedule altogether.Though we live in a 24-hour day, the natural tendency of the body clock is to extend our day beyond 24 hours. It is contrary to our biological programming to shrink our day. That is why travelling in a westward direction is more body-clock friendly than flying east. NASA studies of long haul pilots showed that westward travel was associated with significantly better sleep quantity and quality than eastward flights. When flying west, you are “extending” your day, thus travelling in the natural direction of your internal clock. Flying eastward will involve “shrinking” or reducing your day and is in direct opposition to your internal clock’s natural tendency.One of the more common complaints of travelers is that their sleep becomes disrupted. There are many reasons for this: Changing time zones and schedules, changing light and activity levels, trying to sleep when your body clock is programmed to be awake, disruption of the internal circadian clock and working longer hours. Sleep loss, jet lag and fatigue can seriously affect our ability to function well. Judgment and decision-making can be reduced by 50%, attention by 75 percent, memory by 20 percent and communication by 30 percent. It is often suggested that you adjust your watch as soon as you board a plane, supposedly to try to help you adjust to your destination’s schedule as soon as you arrive. But it can take the body clock several days to several weeks to fully adjust to a new time zone.The main function of the body clock is to_________

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 2.5 K lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Giải các phương trình: x4 + 5x2 + 1 = 0

Toán Lớp 9
Xem chi tiết 6 K lượt xem 2 năm trước
Tổng hợp đề ôn tập thi THPTQG môn Sinh Học có đáp án (Đề số 16)

Tác dụng chính của kĩ thuật nhổ cây con đem cấy là gì?

Sinh học Tốt nghiệp THPT
Xem chi tiết 524 lượt xem 6 năm trước
Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

Read the following passage and mark the latter A, B, C or D on your answer sheet to indicate the word or phrase that best fits each of the numbered blanks . Fill in the appropriate word in question 44      Why is it that many teenagers have the energy to play computer games until late at night but can’t find the energy to get out of bed (35) ________ for school? According to a new report, today’s generation of children are in danger of getting so (36)_______ sleep that they are putting their mental and physical health at (37)_______. Adults can easily survive on seven to eight hours’ sleep a  night, (38)_______teenagers require nine or ten hours. According to medical experts, one in five youngsters (39)________ anything between two and five hours’ sleep a night less than their parents did at their age.      This (40) _____ serious questions about whether lack of sleep is affecting children’s ability to concentrate at school. The connection between sleep deprivation and lapses in memory, impaired reaction time and poor concentration is well (41) _______. Research has shown that losing as little as half an hour’s sleep a night can have profound effects (42) ______how children perform the next day. A good night’s sleep is also crucial for teenagers because it is while they are asleep (43)______ they release a hormone that is essential for their ‘growth spurt’ (the period during teenage years when the body grows at a rapid rate). It’s true that they can, to some (44) ______, catch up on sleep  at weekends, but that won’t help them when they are dropping off to sleep in class on a Friday afternoon.            By Tim Falla and Paul A.Davies, Solutions Advanced. OUP

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1 K lượt xem 6 năm trước
BÀI TẬP TÍNH TOÁN

Hòa tan 1,0 gam quặng crom trong axit, oxi hóa Cr3+ thành CrO72-. Sau khi đã phân hủy hết lượng dư chất oxi hóa, pha loãng dung dịch thành 100ml. Lấy 20 ml dung dịch này cho vào 25 ml dung dịch FeSO4 trong H2SO4. Chuẩn độ lượng dư FeSO4 hết 7,50 ml dung dịch chuẩn K2Cr2O7 0,0150M. Biết rằng 25 ml FeSO4 tương đương với 35 ml dung dịch chuẩn K2Cr2O7. Thành phần % của crom trong quặng là: 

Hóa học Lớp 12
Xem chi tiết 2.3 K lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Giải các phương trình: 2x4 + 3x2 – 2 = 0

Toán Lớp 9
Xem chi tiết 14.9 K lượt xem 2 năm trước
Bài 1: Hàm số lượng giác

Tìm giá trị lớn nhất của hàm số: y = 3 - 2sinx

Toán Lớp 11
Xem chi tiết 45.8 K lượt xem 2 năm trước
Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 10)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase for each of the blanks from 15 to 19About 50 or so kinds modern plastic are made from oil, gas, or coal-non-renewable natural resources. We (15)___ well over three million tons of the stuff in Japan each year and, sooner or later, most of it is thrown away. A high proportion of our animal consumption is in the (16)____ of packaging and this constitutes about seven percent by weight, of our domestic(17) ____ . Almost all of it can be recycled, but very little of it is, though the plastic recycling industry is growing fast. The plastics themselves are extremely energy - rich – they have a higher calorific(18) ____ than coal and one methodn of “recovery” strongly (19)____ by plastic manufacturers if the conversion of waste plastic into a fuel.Điền ô số 19

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 415 lượt xem 6 năm trước
Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

Read the following passage and mark the latter A, B, C or D on your answer sheet to indicate the word or phrase that best fits each of the numbered blanks . Fill in the appropriate word in question 43      Why is it that many teenagers have the energy to play computer games until late at night but can’t find the energy to get out of bed (35) ________ for school? According to a new report, today’s generation of children are in danger of getting so (36)_______ sleep that they are putting their mental and physical health at (37)_______. Adults can easily survive on seven to eight hours’ sleep a  night, (38)_______teenagers require nine or ten hours. According to medical experts, one in five youngsters (39)________ anything between two and five hours’ sleep a night less than their parents did at their age.      This (40) _____ serious questions about whether lack of sleep is affecting children’s ability to concentrate at school. The connection between sleep deprivation and lapses in memory, impaired reaction time and poor concentration is well (41) _______. Research has shown that losing as little as half an hour’s sleep a night can have profound effects (42) ______how children perform the next day. A good night’s sleep is also crucial for teenagers because it is while they are asleep (43)______ they release a hormone that is essential for their ‘growth spurt’ (the period during teenage years when the body grows at a rapid rate). It’s true that they can, to some (44) ______, catch up on sleep  at weekends, but that won’t help them when they are dropping off to sleep in class on a Friday afternoon.            By Tim Falla and Paul A.Davies, Solutions Advanced. OUP

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 756 lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Giải các phương trình: 3x4 – 12x2 + 9 = 0

Toán Lớp 9
Xem chi tiết 11.5 K lượt xem 2 năm trước
Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

Read the following passage and mark the latter A, B, C or D on your answer sheet to indicate the word or phrase that best fits each of the numbered blanks . Fill in the appropriate word in question 42      Why is it that many teenagers have the energy to play computer games until late at night but can’t find the energy to get out of bed (35) ________ for school? According to a new report, today’s generation of children are in danger of getting so (36)_______ sleep that they are putting their mental and physical health at (37)_______. Adults can easily survive on seven to eight hours’ sleep a  night, (38)_______teenagers require nine or ten hours. According to medical experts, one in five youngsters (39)________ anything between two and five hours’ sleep a night less than their parents did at their age.      This (40) _____ serious questions about whether lack of sleep is affecting children’s ability to concentrate at school. The connection between sleep deprivation and lapses in memory, impaired reaction time and poor concentration is well (41) _______. Research has shown that losing as little as half an hour’s sleep a night can have profound effects (42) ______how children perform the next day. A good night’s sleep is also crucial for teenagers because it is while they are asleep (43)______ they release a hormone that is essential for their ‘growth spurt’ (the period during teenage years when the body grows at a rapid rate). It’s true that they can, to some (44) ______, catch up on sleep  at weekends, but that won’t help them when they are dropping off to sleep in class on a Friday afternoon.            By Tim Falla and Paul A.Davies, Solutions Advanced. OUP

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 0.9 K lượt xem 6 năm trước
Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 10)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase for each of the blanks from 15 to 19About 50 or so kinds modern plastic are made from oil, gas, or coal-non-renewable natural resources. We (15)___ well over three million tons of the stuff in Japan each year and, sooner or later, most of it is thrown away. A high proportion of our animal consumption is in the (16)____ of packaging and this constitutes about seven percent by weight, of our domestic(17) ____ . Almost all of it can be recycled, but very little of it is, though the plastic recycling industry is growing fast. The plastics themselves are extremely energy - rich – they have a higher calorific(18) ____ than coal and one methodn of “recovery” strongly (19)____ by plastic manufacturers if the conversion of waste plastic into a fuel.Điền ô số 18

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 371 lượt xem 6 năm trước
Tổng hợp đề ôn tập thi THPTQG môn Sinh Học có đáp án (Đề số 16)

Cho các phát biểu sau về tác động của nhân tố sinh thái lên cá thể sinh vật:(1) Các nhân tố sinh thái tác động một cách tổng hợp lên cá thể sinh vật.(2) Loài có giới hạn sinh thái càng rộng về nhiều nhân tố sinh thái thì càng phân bố hẹp.(3) Các nhân tố sinh thái khác nhau thì tác động lên cá thể sinh vật cũng khác nhau.(4) Các nhân tố sinh thái có thể kìm hãm nhau cũng có thể thúc đẩy nhau khi tác động lên cá thể sinh vật.Số phát biểu đúng là:

Sinh học Tốt nghiệp THPT
Xem chi tiết 487 lượt xem 6 năm trước
30 đề thi thử thpt quốc gia tiếng anh năm 2020 cực hay 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 answer to each of the questions from 28 to 34.Rain pounded down on the roof. I was trying to read but the sound was too loud. I couldn’t help myself from being a little grumpy. I wanted to be outside playing, but the rain was keeping me inside.My mom had gone to the grocery store, and my dad was spending Saturday at the office. I had planned to spend the day hiking, but Mother Nature decided that today was the perfect day for rain.It meant that I would have to entertain myself. I spent most of the morning playing with my stuffed animals and reading. I was sitting next to the window staring out when I got a strange idea: why not just go outside anyway?I put on my boots and a big raincoat and stepped out into the wet world. It was raining hard but it wasn’t cold. All I could hear were raindrops and the wind. I decided to go on my hike anyway.My feet didn’t make any sound on the wet ground and the forest seemed different. I went to my favourite place and sat down. In the summer, my best friend Ellen and I would come here and sit for hours. It was our special place. All of a sudden, I thought I heard someone shouting my name. I turned and saw Ellen walking up behind me.“Oh my Gosh! It’s really you, Martha!” she said. “I can’t believe that you are out here right now. I thought I would be the only person crazy enough to go for a walk in the rain.”I was very happy to have some company. We decided that hiking in the rain was just as fun as hiking in the sunshine. We planned on hiking in the rain again.Question:What does Martha mean when she says “It meant that I would have to entertain myself”?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 491 lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Cho phương trình: x2 - x - 2 = 0Chứng tỏ rằng hai nghiệm tìm được trong câu a) là hoành độ giao điểm của hai đồ thị.

Toán Lớp 9
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Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

Read the following passage and mark the latter A, B, C or D on your answer sheet to indicate the word or phrase that best fits each of the numbered blanks . Fill in the appropriate word in question 41      Why is it that many teenagers have the energy to play computer games until late at night but can’t find the energy to get out of bed (35) ________ for school? According to a new report, today’s generation of children are in danger of getting so (36)_______ sleep that they are putting their mental and physical health at (37)_______. Adults can easily survive on seven to eight hours’ sleep a  night, (38)_______teenagers require nine or ten hours. According to medical experts, one in five youngsters (39)________ anything between two and five hours’ sleep a night less than their parents did at their age.      This (40) _____ serious questions about whether lack of sleep is affecting children’s ability to concentrate at school. The connection between sleep deprivation and lapses in memory, impaired reaction time and poor concentration is well (41) _______. Research has shown that losing as little as half an hour’s sleep a night can have profound effects (42) ______how children perform the next day. A good night’s sleep is also crucial for teenagers because it is while they are asleep (43)______ they release a hormone that is essential for their ‘growth spurt’ (the period during teenage years when the body grows at a rapid rate). It’s true that they can, to some (44) ______, catch up on sleep  at weekends, but that won’t help them when they are dropping off to sleep in class on a Friday afternoon.            By Tim Falla and Paul A.Davies, Solutions Advanced. OUP

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 1 K lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Cho phương trình: x2 - x - 2 = 0.Vẽ hai đồ thị y = x2 và y = x + 2 trên cùng một hệ trục tọa độ

Toán Lớp 9
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Đề luyện thi THPT quốc gia môn tiếng anh có lời giải (Đề số 10)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase for each of the blanks from 15 to 19About 50 or so kinds modern plastic are made from oil, gas, or coal-non-renewable natural resources. We (15)___ well over three million tons of the stuff in Japan each year and, sooner or later, most of it is thrown away. A high proportion of our animal consumption is in the (16)____ of packaging and this constitutes about seven percent by weight, of our domestic(17) ____ . Almost all of it can be recycled, but very little of it is, though the plastic recycling industry is growing fast. The plastics themselves are extremely energy - rich – they have a higher calorific(18) ____ than coal and one methodn of “recovery” strongly (19)____ by plastic manufacturers if the conversion of waste plastic into a fuel.Điền ô số 17

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 342 lượt xem 6 năm trước
Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

Read the following passage and mark the latter A, B, C or D on your answer sheet to indicate the word or phrase that best fits each of the numbered blanks . Fill in the appropriate word in question 40      Why is it that many teenagers have the energy to play computer games until late at night but can’t find the energy to get out of bed (35) ________ for school? According to a new report, today’s generation of children are in danger of getting so (36)_______ sleep that they are putting their mental and physical health at (37)_______. Adults can easily survive on seven to eight hours’ sleep a  night, (38)_______teenagers require nine or ten hours. According to medical experts, one in five youngsters (39)________ anything between two and five hours’ sleep a night less than their parents did at their age.      This (40) _____ serious questions about whether lack of sleep is affecting children’s ability to concentrate at school. The connection between sleep deprivation and lapses in memory, impaired reaction time and poor concentration is well (41) _______. Research has shown that losing as little as half an hour’s sleep a night can have profound effects (42) ______how children perform the next day. A good night’s sleep is also crucial for teenagers because it is while they are asleep (43)______ they release a hormone that is essential for their ‘growth spurt’ (the period during teenage years when the body grows at a rapid rate). It’s true that they can, to some (44) ______, catch up on sleep  at weekends, but that won’t help them when they are dropping off to sleep in class on a Friday afternoon.            By Tim Falla and Paul A.Davies, Solutions Advanced. OUP

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 525 lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Cho phương trình: x2 - x - 2 = 0.Giải phương trình.

Toán Lớp 9
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Tổng hợp đề ôn tập thi THPTQG môn Sinh Học có đáp án (Đề số 16)

Trong các phát biểu sau, có bao nhiêu phát biểu đúng khi nói về dòng năng lượng trong hệ sinh thái.(1) Vi khuẩn phân giải, nấm và một số động vật khong xương sống đóng vai trò truyền năng lượng từ chu trình dinh dưỡng vào môi trường vô sinh.(2) Năng lượng được truyền trong hệ sinh thái theo chu trình tuần hoàn và được sử dụng trở lại.(3) Ở mỗi bậc dinh dưỡng, phần lớn năng lượng bị tiêu hoa do thức ăn được sinh vật sử dụng nhưng không dược đồng hóa.(4) Thực vật đóng vai trò quan trọng trong việc truyền năng lượng từ môi trường vô sinh vào chu trình dinh dưỡng.(5) Một số vi khuẩn đóng vai trò quan trọng trong việc truyền năng lượng từ môi trường vô sinh vào chu trình dinh dưỡng.

Sinh học Tốt nghiệp THPT
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Kỳ thi thử thpt quốc gia lần 1 năm 2019 môn Tiếng Anh cực hay có lời giải(Đề 9)

Read the following passage and mark the latter A, B, C or D on your answer sheet to indicate the word or phrase that best fits each of the numbered blanks . Fill in the appropriate word in question 39      Why is it that many teenagers have the energy to play computer games until late at night but can’t find the energy to get out of bed (35) ________ for school? According to a new report, today’s generation of children are in danger of getting so (36)_______ sleep that they are putting their mental and physical health at (37)_______. Adults can easily survive on seven to eight hours’ sleep a  night, (38)_______teenagers require nine or ten hours. According to medical experts, one in five youngsters (39)________ anything between two and five hours’ sleep a night less than their parents did at their age.      This (40) _____ serious questions about whether lack of sleep is affecting children’s ability to concentrate at school. The connection between sleep deprivation and lapses in memory, impaired reaction time and poor concentration is well (41) _______. Research has shown that losing as little as half an hour’s sleep a night can have profound effects (42) ______how children perform the next day. A good night’s sleep is also crucial for teenagers because it is while they are asleep (43)______ they release a hormone that is essential for their ‘growth spurt’ (the period during teenage years when the body grows at a rapid rate). It’s true that they can, to some (44) ______, catch up on sleep  at weekends, but that won’t help them when they are dropping off to sleep in class on a Friday afternoon.            By Tim Falla and Paul A.Davies, Solutions Advanced. OUP

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 448 lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Vẽ đồ thị của hai hàm số y=14x2 và y=-14x2 trên cùng một hệ trục tọa độ.Tìm trên đồ thị của hàm số  điểm N có cùng hoành độ với M, điểm N’ có cùng hoành độ với M’. Đường thẳng NN’ có song song với Ox không? Vì sao? Tìm tung độ điểm N và N’ bằng hai cách:- Ước lượng trên hình vẽ; - Tính toán theo công thức.

Toán Lớp 9
Xem chi tiết 0.9 K lượt xem 2 năm trước
BÀI TẬP VỀ PHẢN ỨNG ESTE HÓA

Biết rằng phản ứng este hóa CH3COOH+C2H5OH⇌CH3COOC2H5+H2O. Có hằng số nguyên tử cân bằng K = 4, tính % Ancol etylic bị este hóa nếu bắt đầu với [C2H5OH] =1 M, [CH3COOH] = 2M?

Hóa học Lớp 12
Xem chi tiết 630 lượt xem 6 năm trước
Bài 1: Hàm số lượng giác

Tìm giá trị lớn nhất của hàm số: y = 2cosx + 1

Toán Lớp 11
Xem chi tiết 41.4 K lượt xem 2 năm trước
Tổng hợp đề ôn tập thi THPTQG môn Sinh Học có đáp án (Đề số 16)

Quần thể là một tập hợp cá thể

Sinh học Tốt nghiệp THPT
Xem chi tiết 5.8 K lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Vẽ đồ thị của hai hàm số y=14x2 và y=-14x4 trên cùng một hệ trục tọa độ.Đường thẳng đi qua B(0; 4) và song song với trục Ox có dạng : y =4 .Xét phương trình hoành độ giao điểm:14x2=4⇔x2=16⇔x=±4Vậy hoành độ của M là x=-4 và M’ là x =4

Toán Lớp 9
Xem chi tiết 21.7 K lượt xem 2 năm trước
Tổng hợp đề thi thử môn Tiếng Anh có lời giải chi tiết (Đề số 1)

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies. (2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus. (3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals. (4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulate. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.Where do protozoans probably live?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 536 lượt xem 6 năm trước
BÀI TẬP VỀ PHẢN ỨNG ESTE HÓA

Thực hiện phản ứng este hóa m gam CH3COOH bằng 1 lượng vừa đủ C2H5OH thu được 0,02 mol este. Hiệu suất phản ứng H = 60%. Giá trị của m?

Hóa học Lớp 12
Xem chi tiết 2.8 K lượt xem 6 năm trước
Tổng hợp đề ôn tập thi THPTQG môn Sinh Học có đáp án (Đề số 16)

Ý nghĩa về mặt lý luận của định luật Hacđi - Vanbec là

Sinh học Tốt nghiệp THPT
Xem chi tiết 4.1 K lượt xem 6 năm trước
Bài kiểm tra Lipit - Chất béo có lời giải chi tiết (Đề số 1)

Khi thủy phân một triglixerit X ta thu được các axit béo là axit oleic, axit panmitic, axit stearic. Để đốt cháy hoàn toàn 8,6 gam X cần thể tích O2 (ở điều kiện tiêu chuẩn) là

Hóa học Lớp 12
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BÀI TẬP VỀ PHẢN ỨNG ESTE HÓA

Cho 180g axit axetic tác dụng với lượng dư rượu etylic có mặt axit sunfuric đặc làm xúc tác. Ở trạng thái cân bằng, nếu hiệu suất phản ứng là 66% thì khối lượng este thu được là: 

Hóa học Lớp 12
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BÀI TẬP TÍNH TOÁN

Thực hiện phản ứng nhiệt nhôm gồm m gam Al và 4,56 gam Cr2O3 (trong điều kiện không có không khí). Sau khi phản ứng kết thúc thu được hỗn hợp X. Cho toàn bộ X vào một lượng dư dung dịch HCl loãng (nóng), sau khi phản ứng xảy ra hoàn toàn thu được 2,016 lít H2 (đktc). Còn nếu cho X vào một lượng dư dung dịch NaOH đặc nóng, sau khi phản ứng kết thúc thì số mol NaOH đã dùng là

Hóa học Lớp 12
Xem chi tiết 1 K lượt xem 6 năm trước
30 đề thi thử thpt quốc gia tiếng anh năm 2020 cực hay 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 answer to each of the questions from 28 to 34.Rain pounded down on the roof. I was trying to read but the sound was too loud. I couldn’t help myself from being a little grumpy. I wanted to be outside playing, but the rain was keeping me inside.My mom had gone to the grocery store, and my dad was spending Saturday at the office. I had planned to spend the day hiking, but Mother Nature decided that today was the perfect day for rain.It meant that I would have to entertain myself. I spent most of the morning playing with my stuffed animals and reading. I was sitting next to the window staring out when I got a strange idea: why not just go outside anyway?I put on my boots and a big raincoat and stepped out into the wet world. It was raining hard but it wasn’t cold. All I could hear were raindrops and the wind. I decided to go on my hike anyway.My feet didn’t make any sound on the wet ground and the forest seemed different. I went to my favourite place and sat down. In the summer, my best friend Ellen and I would come here and sit for hours. It was our special place. All of a sudden, I thought I heard someone shouting my name. I turned and saw Ellen walking up behind me.“Oh my Gosh! It’s really you, Martha!” she said. “I can’t believe that you are out here right now. I thought I would be the only person crazy enough to go for a walk in the rain.”I was very happy to have some company. We decided that hiking in the rain was just as fun as hiking in the sunshine. We planned on hiking in the rain again.Question:What was keeping Martha inside?

Tiếng Anh Tốt nghiệp THPT
Xem chi tiết 675 lượt xem 6 năm trước
Ôn tập chương 4 (Câu hỏi - Bài tập)

Nêu cách giải phương trình trùng phương ax4 + bx2 + c = 0 (a ≠ 0)

Toán Lớp 9
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BÀI TẬP VỀ PHẢN ỨNG ESTE HÓA

Thực hiện phản ứng este hóa 9,2g glixerol với 60g axit axetic. Giả sử chỉ thu được glixerol triaxetat có khối lượng 17,44 g. Tính hiệu suất của phản ứng este hóa:

Hóa học Lớp 12
Xem chi tiết 2.7 K lượt xem 6 năm trước
BÀI TẬP TÍNH TOÁN

Khí H2S tác dụng với dung dịch chứa K2Cr2O7 và H2SO4 tạo nên kết tủa A. Kết tủa này cháy trong O2 tạo nên một khí có mùi khó chịu. Hòa tan khí này vào nước thu được 100 gam dung dịch axit 8,2%. Khối lượng K2Cr2O7 đã tác dụng với H2S là?

Hóa học Lớp 12
Xem chi tiết 689 lượt xem 6 năm trước

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