Read the following passage and mark the letter A, B, C, or D on your answer answer to each of the questions

An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled – a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions. Many of more important air pollutants such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentrations of these pollutants were altered by various chemical reactions; they became components in biogeochemical cycle. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil on a global basis, nature's output of these compounds dwarfs that resulting from human activities.

However, human production usually occurs in a localized area, such as a city. In this localized regions, human output may be dominant and may temporarily overload the natural purification scheme of the cycle. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, as a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.

The word "these" in the second paragraph is closest in meaning to

Read the following passage and mark the letter A, B, C, or D on your answer answer to each of the questions

An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled – a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions. Many of more important air pollutants such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentrations of these pollutants were altered by various chemical reactions; they became components in biogeochemical cycle. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil on a global basis, nature's output of these compounds dwarfs that resulting from human activities.

However, human production usually occurs in a localized area, such as a city. In this localized regions, human output may be dominant and may temporarily overload the natural purification scheme of the cycle. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, as a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.

For which of the following reasons can natural pollutants play an important role in controlling air pollution?

Read the following passage and mark the letter A, B, C, or D on your answer answer to each of the questions

An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled – a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions. Many of more important air pollutants such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentrations of these pollutants were altered by various chemical reactions; they became components in biogeochemical cycle. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil on a global basis, nature's output of these compounds dwarfs that resulting from human activities.

However, human production usually occurs in a localized area, such as a city. In this localized regions, human output may be dominant and may temporarily overload the natural purification scheme of the cycle. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, as a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.

What does the passage mainly discuss?

Read the following passage and mark the letter A, B, C, or D on your answer answer to each of the questions

An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled – a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions. Many of more important air pollutants such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentrations of these pollutants were altered by various chemical reactions; they became components in biogeochemical cycle. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil on a global basis, nature's output of these compounds dwarfs that resulting from human activities.

However, human production usually occurs in a localized area, such as a city. In this localized regions, human output may be dominant and may temporarily overload the natural purification scheme of the cycle. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, as a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.

The word "localized” 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 word or phrase that best fits each of the numbered blanks

Schools in the United States have not always had a large number of libraries. As recently as 1958 about half of the public schools in the United States had no libraries at all. The (17)_______of public school libraries increased dramatically when the federal government passed the Elementary and Secondary Education Act of 1965, which provided funds for school districts to improve their education programs and facilities, including their libraries. (18) _______, many educators claim that since the legislation was passed federal spending has not increased sufficiently to meet the rising cost of new library technologies such as computer databases and Internet access.

Because the federal government provides only limited funds to schools, individual school districts (19)______ on funds from local property taxes to meet the vast majority of public schools tend to reflect the financial capabilities of the communities in which they are located. Districts in wealthy suburbs often have fully staffed libraries (20)________ abundant resources, spacious facilities, and curricular and instructional support. In (21) __________school districts in many poor areas house their libraries in ordinary classrooms or in small rooms. The libraries in such areas are generally staffed by volunteers, who organize and maintain books that are often out-of-date, irrelevant, or damaged.

Question 20

Mark the letter A, B, C. or D on your answer sheet to indicate the most suitable response to each of the following sentences

Tom: "Do you think it's going to rain?” - Trump: “_______”

Read the following passage and mark the letter A, B, C, or D on your answer answer to each of the questions

An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled – a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions. Many of more important air pollutants such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentrations of these pollutants were altered by various chemical reactions; they became components in biogeochemical cycle. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil on a global basis, nature's output of these compounds dwarfs that resulting from human activities.

However, human production usually occurs in a localized area, such as a city. In this localized regions, human output may be dominant and may temporarily overload the natural purification scheme of the cycle. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, as a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.

The word "detectable" in the third paragraph is closest in meaning to