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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.Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants.The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them.In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms.The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season.With what topic does this passage primarily deal?
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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 48
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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 47
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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 46
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 45 to 54.POLAR BEARSPolar bears are in danger of dying out. (45) _________ some other endangered animals, it’s not hunters that are the problem, it’s climate change. Since 1979, the ice cap at the Arctic Circle where the polar bears live has (46) _________ in size by about 30 percent. The temperature in the Arctic has slowly been (47) _________ and this is (48) _________ the sea ice to melt, endangering the polar bears’ home.The polar bears’ main (49) _________ of food are the different types of seal found in the Arctic. They catch them by waiting next to the air holes the seals have (50) _________in the ice. (51) _________ the bears are very strong swimmers, they could never catch seals in the water. This means that the bears (52) _________ do rely on the ice to hunt.Polar bears also need sea ice to travel. They can (53) _________ a huge territory and often swim from one part of the ice to another. They have been known to swim up to 100km, but when there is less ice, they may have to swim further and this can (54) _________ fatal to the bears. A number of bears have drowned in the last few years and scientists believe that it is because they were not able to reach more sea ice before they became too tired and couldn’t swim any further.Điền vào ô 45
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 35 to 42.Social networksBusiness applicationsSocial networks connect people at low cost; this can be beneficial for entrepreneurs and small businesses looking to expand their contact base. These networks often act as a customer relationship management tool for companies selling products and services. Companies can also use social networks for advertising in the form of banners and text ads. Since businesses operate globally, social networks can make it easier to keep in touch with contacts around the world.Medical applicationsSocial networks are beginning to be adopted by healthcare professionals as a means to manage institutional knowledge, disseminate peer to peer knowledge and to highlight individual physicians and institutions. The advantage of using a dedicated medical social networking site is that all the members are screened against the state licensing board list of practitioners. The role of social networks is especially of interest to pharmaceutical companies who spend approximately “32 percent of their marketing dollars” attempting to influence the opinion leaders of social networks.Languages, nationalities and academiaVarious social networking sites have sprung up catering to different languages and countries. The popular site Facebook has been cloned for various countries and languages and some specializing in connecting students and faculty.Social networks for social goodSeveral websites are beginning to tap into the power of the social networking model for social good. Such models may be highly successful for connecting otherwise fragmented industries and small organizations without the resources to reach a broader audience with interested and passionate users. Users benefit by interacting with a like-minded community and finding a channel for their energy and giving.Business modelFew social networks currently charge money for membership. In part, this may be because social networking is a relatively new service, and the value of using them has not been firmly established in customers' minds. Companies such as MySpace and Facebook sell online advertising on their site. Hence, they are seeking large memberships, and charging for membership would be counter productive. Some believe that the deeper information that the sites have on each user will allow much better targeted advertising than any other site can currently provide. Sites are also seeking other ways to make money, such as by creating an online marketplace or by selling professional information and social connections to businesses.Privacy issuesOn large social networking services, there have been growing concerns about users giving out too much personal information and the threat of sexual predators. Users of these services need to be aware of data theft or viruses. However, large services, such as MySpace, often work with law enforcement to try to prevent such incidents. In addition, there is a perceived privacy threat in relation to placing too much personal information in the hands of large corporations or governmental bodies, allowing a profile to be produced on an individual's behavior on which decisions, detrimental to an individual, may be taken.InvestigationsSocial network services are increasingly being used in legal and criminal investigations. Information posted on sites such as MySpace and Facebook, has been used by police, probation, and university officials to prosecute users of said sites. In some situations, content posted on MySpace has been used in court.Why do advertisers like social network sites?
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 35 to 42.Social networksBusiness applicationsSocial networks connect people at low cost; this can be beneficial for entrepreneurs and small businesses looking to expand their contact base. These networks often act as a customer relationship management tool for companies selling products and services. Companies can also use social networks for advertising in the form of banners and text ads. Since businesses operate globally, social networks can make it easier to keep in touch with contacts around the world.Medical applicationsSocial networks are beginning to be adopted by healthcare professionals as a means to manage institutional knowledge, disseminate peer to peer knowledge and to highlight individual physicians and institutions. The advantage of using a dedicated medical social networking site is that all the members are screened against the state licensing board list of practitioners. The role of social networks is especially of interest to pharmaceutical companies who spend approximately “32 percent of their marketing dollars” attempting to influence the opinion leaders of social networks.Languages, nationalities and academiaVarious social networking sites have sprung up catering to different languages and countries. The popular site Facebook has been cloned for various countries and languages and some specializing in connecting students and faculty.Social networks for social goodSeveral websites are beginning to tap into the power of the social networking model for social good. Such models may be highly successful for connecting otherwise fragmented industries and small organizations without the resources to reach a broader audience with interested and passionate users. Users benefit by interacting with a like-minded community and finding a channel for their energy and giving.Business modelFew social networks currently charge money for membership. In part, this may be because social networking is a relatively new service, and the value of using them has not been firmly established in customers' minds. Companies such as MySpace and Facebook sell online advertising on their site. Hence, they are seeking large memberships, and charging for membership would be counter productive. Some believe that the deeper information that the sites have on each user will allow much better targeted advertising than any other site can currently provide. Sites are also seeking other ways to make money, such as by creating an online marketplace or by selling professional information and social connections to businesses.Privacy issuesOn large social networking services, there have been growing concerns about users giving out too much personal information and the threat of sexual predators. Users of these services need to be aware of data theft or viruses. However, large services, such as MySpace, often work with law enforcement to try to prevent such incidents. In addition, there is a perceived privacy threat in relation to placing too much personal information in the hands of large corporations or governmental bodies, allowing a profile to be produced on an individual's behavior on which decisions, detrimental to an individual, may be taken.InvestigationsSocial network services are increasingly being used in legal and criminal investigations. Information posted on sites such as MySpace and Facebook, has been used by police, probation, and university officials to prosecute users of said sites. In some situations, content posted on MySpace has been used in court.According to the text, social networks
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 30 to 34. As heart disease continues to be the number-one killer in the United States, researchers have become increasingly interested in identifying the potential risk factors that trigger heart attacks. High-fat diets and „life in the fast lane” have long been known to contribute to the high incidence of heart failure. But according to new studies, the list of risk factors may be significantly longer and quite surprising. Heart failure, for example appears to have seasonal and temporal patterns. A higher percentage of heart attacks occur in cold weather, and more people experience heart failure on Monday than on any other day of the week. In addition, people are more susceptible to heart attacks in the first few hours after waking. Cardiologists first observed this morning phenomenon in the mid-1980s and have since discovered a number of possible causes. An early-morning rise in blood pressure, heart rate, and concentration of heart-stimulating hormones, plus a reduction of blood flow to the heart, may all contribute to the higher incidence of heart attacks between the hours of 8:00 A.M and 10 A.M. In other studies, both birthdays and bachelorhood have been implicated as risk factors. Statistics reveal that heart attack rates increase significantly for both females and males in the few days immediately preceding and following their birthdays. And unmarried men are more at risk for heart attacks than their married counterparts. Though stress is thought to be linked in some way to all of the aforementioned risk factors, intense research continues in the hope of further comprehending why and how heart failure is triggered.Which of the following does the passage infer?
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 30 to 34. As heart disease continues to be the number-one killer in the United States, researchers have become increasingly interested in identifying the potential risk factors that trigger heart attacks. High-fat diets and „life in the fast lane” have long been known to contribute to the high incidence of heart failure. But according to new studies, the list of risk factors may be significantly longer and quite surprising. Heart failure, for example appears to have seasonal and temporal patterns. A higher percentage of heart attacks occur in cold weather, and more people experience heart failure on Monday than on any other day of the week. In addition, people are more susceptible to heart attacks in the first few hours after waking. Cardiologists first observed this morning phenomenon in the mid-1980s and have since discovered a number of possible causes. An early-morning rise in blood pressure, heart rate, and concentration of heart-stimulating hormones, plus a reduction of blood flow to the heart, may all contribute to the higher incidence of heart attacks between the hours of 8:00 A.M and 10 A.M. In other studies, both birthdays and bachelorhood have been implicated as risk factors. Statistics reveal that heart attack rates increase significantly for both females and males in the few days immediately preceding and following their birthdays. And unmarried men are more at risk for heart attacks than their married counterparts. Though stress is thought to be linked in some way to all of the aforementioned risk factors, intense research continues in the hope of further comprehending why and how heart failure is triggered.Which of the following is NOT cited as a possible risk factor?
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 30 to 34. As heart disease continues to be the number-one killer in the United States, researchers have become increasingly interested in identifying the potential risk factors that trigger heart attacks. High-fat diets and „life in the fast lane” have long been known to contribute to the high incidence of heart failure. But according to new studies, the list of risk factors may be significantly longer and quite surprising. Heart failure, for example appears to have seasonal and temporal patterns. A higher percentage of heart attacks occur in cold weather, and more people experience heart failure on Monday than on any other day of the week. In addition, people are more susceptible to heart attacks in the first few hours after waking. Cardiologists first observed this morning phenomenon in the mid-1980s and have since discovered a number of possible causes. An early-morning rise in blood pressure, heart rate, and concentration of heart-stimulating hormones, plus a reduction of blood flow to the heart, may all contribute to the higher incidence of heart attacks between the hours of 8:00 A.M and 10 A.M. In other studies, both birthdays and bachelorhood have been implicated as risk factors. Statistics reveal that heart attack rates increase significantly for both females and males in the few days immediately preceding and following their birthdays. And unmarried men are more at risk for heart attacks than their married counterparts. Though stress is thought to be linked in some way to all of the aforementioned risk factors, intense research continues in the hope of further comprehending why and how heart failure is triggered.The phrase “susceptible to” could best be replaced by
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 30 to 34. As heart disease continues to be the number-one killer in the United States, researchers have become increasingly interested in identifying the potential risk factors that trigger heart attacks. High-fat diets and „life in the fast lane” have long been known to contribute to the high incidence of heart failure. But according to new studies, the list of risk factors may be significantly longer and quite surprising. Heart failure, for example appears to have seasonal and temporal patterns. A higher percentage of heart attacks occur in cold weather, and more people experience heart failure on Monday than on any other day of the week. In addition, people are more susceptible to heart attacks in the first few hours after waking. Cardiologists first observed this morning phenomenon in the mid-1980s and have since discovered a number of possible causes. An early-morning rise in blood pressure, heart rate, and concentration of heart-stimulating hormones, plus a reduction of blood flow to the heart, may all contribute to the higher incidence of heart attacks between the hours of 8:00 A.M and 10 A.M. In other studies, both birthdays and bachelorhood have been implicated as risk factors. Statistics reveal that heart attack rates increase significantly for both females and males in the few days immediately preceding and following their birthdays. And unmarried men are more at risk for heart attacks than their married counterparts. Though stress is thought to be linked in some way to all of the aforementioned risk factors, intense research continues in the hope of further comprehending why and how heart failure is triggered.In line 2, the word “potential” could best be replaced by which of the following?
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 30 to 34. As heart disease continues to be the number-one killer in the United States, researchers have become increasingly interested in identifying the potential risk factors that trigger heart attacks. High-fat diets and „life in the fast lane” have long been known to contribute to the high incidence of heart failure. But according to new studies, the list of risk factors may be significantly longer and quite surprising. Heart failure, for example appears to have seasonal and temporal patterns. A higher percentage of heart attacks occur in cold weather, and more people experience heart failure on Monday than on any other day of the week. In addition, people are more susceptible to heart attacks in the first few hours after waking. Cardiologists first observed this morning phenomenon in the mid-1980s and have since discovered a number of possible causes. An early-morning rise in blood pressure, heart rate, and concentration of heart-stimulating hormones, plus a reduction of blood flow to the heart, may all contribute to the higher incidence of heart attacks between the hours of 8:00 A.M and 10 A.M. In other studies, both birthdays and bachelorhood have been implicated as risk factors. Statistics reveal that heart attack rates increase significantly for both females and males in the few days immediately preceding and following their birthdays. And unmarried men are more at risk for heart attacks than their married counterparts. Though stress is thought to be linked in some way to all of the aforementioned risk factors, intense research continues in the hope of further comprehending why and how heart failure is triggered.What does the passage mainly discuss?