Nếu thiết diện của một hình hộp và một mặt phẳng là một đa giác thì đa giác đó có nhiều nhất mấy cạnh?        

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:

There are a number of natural disasters that can strike across the globe. Two that are frequently linked to one another are earthquakes and tsunamis. Both of them can cause a great amount of devastation when they hit. However, tsunamis are the direct result of earthquakes and cannot happen without them.

The Earth has three main parts. They are the crust, the mantle, and the core. The crust is the outer layer of the Earth. It is not a single piece of land. Instead, it is comprised of a number of plates. There are a few enormous plates and many smaller ones. These plates essentially rest upon the mantle, which is fluid. As a result, the plates are in constant - yet slow - motion. The plates may move away from or toward other plates. In some cases, they collide violently with the plates adjoining them. The movement of the plates causes tension in the rock. Over a long time, this tension may build up. When it is released, an earthquake happens.

Tens of thousands of earthquakes happen every year. The vast majority are so small that only scientific instruments can perceive them. Others are powerful enough that people can feel them, yet they cause little harm or damage. More powerful earthquakes, however, can cause buildings, bridges, and other structures to collapse. They may additionally injure and kill thousands of people and might even cause the land to change its appearance.

Since most of the Earth’s surface is water, numerous earthquakes happen beneath the planet’s oceans. Underwater earthquakes can cause the seafloor to move. This results in the displacement of water in the ocean. When this occurs, a tsunami may form. This is a wave that forms on the surface and moves in all directions from the place where the earthquake happened. A tsunami moves extremely quickly and can travel thousands of kilometres. As it approaches land, the water near the coast gets sucked out to sea. This causes the tsunami to increase in height. Minutes later, the tsunami arrives. A large tsunami - one more than ten meters in height - can travel far inland. As it does that, it can flood the land, destroy human settlements, and kill large numbers of people.

Question: What is the passage mainly about?  

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:

There are a number of natural disasters that can strike across the globe. Two that are frequently linked to one another are earthquakes and tsunamis. Both of them can cause a great amount of devastation when they hit. However, tsunamis are the direct result of earthquakes and cannot happen without them.

The Earth has three main parts. They are the crust, the mantle, and the core. The crust is the outer layer of the Earth. It is not a single piece of land. Instead, it is comprised of a number of plates. There are a few enormous plates and many smaller ones. These plates essentially rest upon the mantle, which is fluid. As a result, the plates are in constant - yet slow - motion. The plates may move away from or toward other plates. In some cases, they collide violently with the plates adjoining them. The movement of the plates causes tension in the rock. Over a long time, this tension may build up. When it is released, an earthquake happens.

Tens of thousands of earthquakes happen every year. The vast majority are so small that only scientific instruments can perceive them. Others are powerful enough that people can feel them, yet they cause little harm or damage. More powerful earthquakes, however, can cause buildings, bridges, and other structures to collapse. They may additionally injure and kill thousands of people and might even cause the land to change its appearance.

Since most of the Earth’s surface is water, numerous earthquakes happen beneath the planet’s oceans. Underwater earthquakes can cause the seafloor to move. This results in the displacement of water in the ocean. When this occurs, a tsunami may form. This is a wave that forms on the surface and moves in all directions from the place where the earthquake happened. A tsunami moves extremely quickly and can travel thousands of kilometres. As it approaches land, the water near the coast gets sucked out to sea. This causes the tsunami to increase in height. Minutes later, the tsunami arrives. A large tsunami - one more than ten meters in height - can travel far inland. As it does that, it can flood the land, destroy human settlements, and kill large numbers of people.

Question: The word “It” in bold in paragraph 2 refers to ________.         

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:

A survey is a study, generally in the form of an interview or a ques­tionnaire, which provides information concerning how people think and act. In the United States, the best-known surveys are the Gallup poll and the Harris poll. As anyone who watches the news during presiden­tial campaigns knows, these polls have become an important part of political life in the United States.

North Americans are familiar with the many "person on the street" interviews on local television news shows. While such interviews can be highly entertaining, they are not necessarily an accurate indication of public opinion. First, they reflect the opinions of only those people who appear at a certain location. Thus, such samples can be biased in favor of commuters, middle-class shoppers, or factory workers, depending on which area the new people select. Second, television interviews tend to attract outgoing people who are willing to appear on the air, while they frighten away others who may feel intimidated by a camera. A survey must be based on a precise, representative sampling if it is to genu­inely reflect a broad range of the population.

In preparing to conduct a survey, sociologists must exercisegreat care in the wording of questions. An effective survey question must be simple and clear enough for people to understand it. It must also be specific enough so that there are no problems in interpreting the re­sults. Even questions that are less structured must be carefully phrased in order to elicitthe type of information desired. Surveys can be indispensable sources of information, but only if the sampling is done properly and the questions are worded accurately.

There are two main forms of surveys: the interview and the ques­tionnaire. Each of these forms of survey research has its advantages. An interviewer can obtain a high response rate because people find it more difficult to turn down a personal request for an interview than to throw away a written questionnaire. In addition, an interviewer can go beyond written questions and probefor a subject's underlying feelings and reasons. However, questionnaires have the advantage of being cheaper and more consistent.

Question 46: Which of the following terms is defined in the passage?          

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:

A survey is a study, generally in the form of an interview or a ques­tionnaire, which provides information concerning how people think and act. In the United States, the best-known surveys are the Gallup poll and the Harris poll. As anyone who watches the news during presiden­tial campaigns knows, these polls have become an important part of political life in the United States.

North Americans are familiar with the many "person on the street" interviews on local television news shows. While such interviews can be highly entertaining, they are not necessarily an accurate indication of public opinion. First, they reflect the opinions of only those people who appear at a certain location. Thus, such samples can be biased in favor of commuters, middle-class shoppers, or factory workers, depending on which area the new people select. Second, television interviews tend to attract outgoing people who are willing to appear on the air, while they frighten away others who may feel intimidated by a camera. A survey must be based on a precise, representative sampling if it is to genu­inely reflect a broad range of the population.

In preparing to conduct a survey, sociologists must exercisegreat care in the wording of questions. An effective survey question must be simple and clear enough for people to understand it. It must also be specific enough so that there are no problems in interpreting the re­sults. Even questions that are less structured must be carefully phrased in order to elicitthe type of information desired. Surveys can be indispensable sources of information, but only if the sampling is done properly and the questions are worded accurately.

There are two main forms of surveys: the interview and the ques­tionnaire. Each of these forms of survey research has its advantages. An interviewer can obtain a high response rate because people find it more difficult to turn down a personal request for an interview than to throw away a written questionnaire. In addition, an interviewer can go beyond written questions and probefor a subject's underlying feelings and reasons. However, questionnaires have the advantage of being cheaper and more consistent.

Question 47: The word "exercise" in line 15 is closest in meaning to         

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:

Are organically grown foods the best choices? The advantage claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods - a term whose meaning varies greatly - frequently proclaim that such products are safer and more nutritious than others. The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional evidence, the preponderance of written material advancing. As a result, claims that eating a diet consisting of entirely organically grown foods prevents or cures diseases provides other benefits to health have become widely publicized and form the basis for folklore. Almost daily, the public is besieged by claims for “no - aging” diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural to unfertilized eggs, that untreated grains are better than fumigated grains, and the like. One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases, consumers misled if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern if consumers particularly those with limited incomes, distrust the regular food supply and buy only expensive organic foods instead.

Question 50: What is the author’s attitude toward the claims made by advocates of health foods?         

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:

Are organically grown foods the best choices? The advantage claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods - a term whose meaning varies greatly - frequently proclaim that such products are safer and more nutritious than others. The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional evidence, the preponderance of written material advancing. As a result, claims that eating a diet consisting of entirely organically grown foods prevents or cures diseases provides other benefits to health have become widely publicized and form the basis for folklore. Almost daily, the public is besieged by claims for “no - aging” diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural to unfertilized eggs, that untreated grains are better than fumigated grains, and the like. One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases, consumers misled if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern if consumers particularly those with limited incomes, distrust the regular food supply and buy only expensive organic foods instead.

Question 47: The word “maintain” in the last paragraph is closest in meaning to______.  

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:

Are organically grown foods the best choices? The advantage claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods - a term whose meaning varies greatly - frequently proclaim that such products are safer and more nutritious than others. The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional evidence, the preponderance of written material advancing. As a result, claims that eating a diet consisting of entirely organically grown foods prevents or cures diseases provides other benefits to health have become widely publicized and form the basis for folklore. Almost daily, the public is besieged by claims for “no - aging” diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural to unfertilized eggs, that untreated grains are better than fumigated grains, and the like. One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases, consumers misled if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern if consumers particularly those with limited incomes, distrust the regular food supply and buy only expensive organic foods instead.

Question 46: The word “unsubstantiated” in paragraph 3 is closest in meaning to________.         

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:

Are organically grown foods the best choices? The advantage claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods - a term whose meaning varies greatly - frequently proclaim that such products are safer and more nutritious than others. The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional evidence, the preponderance of written material advancing. As a result, claims that eating a diet consisting of entirely organically grown foods prevents or cures diseases provides other benefits to health have become widely publicized and form the basis for folklore. Almost daily, the public is besieged by claims for “no - aging” diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural to unfertilized eggs, that untreated grains are better than fumigated grains, and the like. One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases, consumers misled if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern if consumers particularly those with limited incomes, distrust the regular food supply and buy only expensive organic foods instead.

Question 49: According to the last paragraph, consumers who believe that organic foods are better than conventionally grown foods are often _____________.         

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:

Are organically grown foods the best choices? The advantage claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods - a term whose meaning varies greatly - frequently proclaim that such products are safer and more nutritious than others. The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional evidence, the preponderance of written material advancing. As a result, claims that eating a diet consisting of entirely organically grown foods prevents or cures diseases provides other benefits to health have become widely publicized and form the basis for folklore. Almost daily, the public is besieged by claims for “no - aging” diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural to unfertilized eggs, that untreated grains are better than fumigated grains, and the like. One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases, consumers misled if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern if consumers particularly those with limited incomes, distrust the regular food supply and buy only expensive organic foods instead.

Question 48: The author implies that there is cause for concern if consumers with limited incomes buy organic foods instead of conventionally grown foods because ______.             

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 that follow:

Although only a small percentage of the electromagnetic radiation that is emitted by the Sun is ultraviolet (UV) radiation, the amount that is emitted would be enough to cause severe damage to most forms of life on Earth were it all to reach the surface of the Earth. Fortunately, all of the Sun’s ultraviolet radiation does not reach the Earth because of a layer of oxygen, called the ozone layer encircling the Earth in the stratosphere at an altitude of about 15 miles above the Earth. The ozone layer absorbs much of the Sun’s ultraviolet radiation and prevents it from reaching the Earth. Ozone is a form of oxygen in which each molecule consists of three atoms (O3) instead of the two atoms (O2) usually found in an oxygen molecule. Ozone forms in the stratosphere in a process that is initiated by ultraviolet radiation from the Sun. UV radiation from the Sun splits oxygen molecules with two atoms into free oxygen atoms, and each of these unattached oxygen atoms then joins up with an oxygen molecule to form ozone. UV radiation is also capable of splitting up ozone molecules; thus, ozone is constantly forming, splitting, and reforming in the stratosphere. When UV radiation is absorbed during the process of ozone formation and reformation, it is unable to reach Earth and cause damage there. Recently, however, the ozone layer over parts of the Earth has been diminishing. Chief among the culprits in the case of the disappearing ozone, those that are really responsible, are the chlorofluorocarbons (CFCs). CFCs meander up from Earth into the stratosphere, where they break down and release chlorine. The released chlorine reacts with ozone in the stratosphere to form chlorine monoxide (CIO) and oxygen (O2). The chlorine then becomes free to go through the cycle over and over again. One chlorine atom can, in fact, destroy hundreds of thousands of ozone molecules in this repetitious cycle, and the effects of this destructive process are now becoming evident. 

Question: According to the passage, ultraviolet radiation from the Sun..............