Cho hình chóp  có đáy  là tam giác vuông cân tại ,  và  góc giữa đường thẳng  và mặt phẳng  bằng  Tính thể tích  của khối chóp đã cho.        

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 44: The “welcome development” mentioned in paragraph 2 is an increase in ____.         

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:

Computers have led to a greater change in our society in recent decades than any other force and are likely to continue to do so until the next century. The industry surrounding computers is growing quickly, providing employment for many but meanwhile making others redundant. Jobs that computers can do much more reliably, faster and cheaper are lost. The redeployment of labour and the prospect of increased leisure are causing social upheavals which require new ideas and significant changes of attitude.

Question 41: As implied in the passage, the widespread use of computers in industry _______.         

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:

Computers have led to a greater change in our society in recent decades than any other force and are likely to continue to do so until the next century. The industry surrounding computers is growing quickly, providing employment for many but meanwhile making others redundant. Jobs that computers can do much more reliably, faster and cheaper are lost. The redeployment of labour and the prospect of increased leisure are causing social upheavals which require new ideas and significant changes of attitude.

Question 40: According to the passage, the impact computers have had on society ___________.         

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 43: The word “others” in paragraph 1 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:

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 42: The word “advocates” in paragraph 1 is closest in meaning to 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:

Computers have led to a greater change in our society in recent decades than any other force and are likely to continue to do so until the next century. The industry surrounding computers is growing quickly, providing employment for many but meanwhile making others redundant. Jobs that computers can do much more reliably, faster and cheaper are lost. The redeployment of labour and the prospect of increased leisure are causing social upheavals which require new ideas and significant changes of attitude.

Question 39: It is pointed out in the passage that the introduction of computers into daily life __________________.  

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: It is stated in the passage that the ozone layer……………  

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: The pronoun “it” 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 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: The word “culprits'' in paragraph 3 is closest in meaning to 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 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, what happens after a chlorine molecule reacts with an ozone molecule?