Câu hỏi:

11/09/2024 488

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

A. the various chemical reactions

B. the pollutants from the developing Earth

C. the compounds mover to the water or soil

D. the components in biogeochemical cycles

Đáp án chính xác

Trả lời:

verified Giải bởi Vietjack

Đáp án D

Theo thông tin bài văn cung cấp, ta thấy: "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."

Dịch nghĩa:

“Một chất ô nhiễm không khí được định nghĩa là một hợp chất do con người thêm vào trực tiếp hoặc gián tiếp vào khí quyển với số lượng đủ để ảnh hưởng xấu đến con người, động vật, thực vật hoặc vật liệu. Ô nhiễm không khí yêu cầu một định nghĩa rất linh hoạt cho phép thay đổi liên tục. Khi các luật về ô nhiễm không khí đầu tiên được thiết lập ở Anh vào thế kỷ 14, các chất ô nhiễm không khí bị hạn chế chỉ là các hợp chất có thể nhìn thấy hoặc ngửi thấy – điều này rất khác so với danh sách dài các chất độc hại hiện nay. Khi công nghệ phát triển và kiến thức về các khía cạnh sức khỏe của các hóa chất khác nhau gia tăng, danh sách các chất ô nhiễm không khí đã dài hơn. Trong tương lai, ngay cả hơi nước cũng có thể được coi là một chất ô nhiễm không khí trong những điều kiện nhất định. Nhiều chất ô nhiễm không khí quan trọng hơn như oxit lưu huỳnh, carbon monoxide và oxit nitơ, có sẵn trong tự nhiên. Khi Trái Đất phát triển, nồng độ của các chất ô nhiễm này đã bị thay đổi bởi các phản ứng hóa học khác nhau; chúng trở thành các thành phần trong chu trình sinh học. Chúng hoạt động như một hệ thống lọc không khí bằng cách cho phép các hợp chất di chuyển từ không khí đến nước hoặc đất trên cơ sở toàn cầu, sản lượng tự nhiên của các hợp chất này vượt xa so với sản lượng từ các hoạt động của con người.

Tuy nhiên, sản xuất của con người thường xảy ra ở những khu vực cục bộ, chẳng hạn như thành phố. Trong những khu vực cục bộ này, sản lượng của con người có thể chiếm ưu thế và có thể tạm thời quá tải hệ thống lọc tự nhiên của chu trình. Kết quả là nồng độ các hóa chất độc hại trong không khí gia tăng. Nồng độ mà các tác động xấu xuất hiện sẽ lớn hơn nồng độ mà các chất ô nhiễm có trong sự vắng mặt của các hoạt động của con người. Nồng độ thực tế không cần phải lớn để một chất trở thành chất ô nhiễm; thực tế, giá trị số lượng cho chúng ta biết rất ít cho đến khi chúng ta biết mức độ gia tăng này so với nồng độ mà sẽ xảy ra tự nhiên trong khu vực. Ví dụ, sulfur dioxide có tác động sức khỏe phát hiện được ở 0,08 phần triệu (ppm), điều này gấp khoảng 400 lần mức độ tự nhiên của nó. Carbon monoxide, tuy nhiên, có mức độ tự nhiên là 0,1 ppm và không thường là chất ô nhiễm cho đến khi mức độ của nó đạt khoảng 15 ppm.”

CÂU HỎI HOT CÙNG CHỦ ĐỀ

Câu 1:

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 "adversely" is closest in meaning to

Xem đáp án » 21/07/2024 491

Câu 2:

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 17

Xem đáp án » 18/07/2024 462

Câu 3:

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?

Xem đáp án » 18/07/2024 264

Câu 4:

Mark the letter A, B, C, or D on your answer answer sheet to indicate the underlined part that needs correction in each of the questions

Each of the beautiful cars in the shop was quickly sold to their owner

Xem đáp án » 18/07/2024 257

Câu 5:

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 19

Xem đáp án » 20/07/2024 223

Câu 6:

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?

Xem đáp án » 18/07/2024 197

Câu 7:

Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions

Xem đáp án » 18/07/2024 169

Câu 8:

Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions

Xem đáp án » 18/07/2024 166

Câu 9:

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 team reached the top of the mountain. The team spent a night there.

Xem đáp án » 18/07/2024 166

Câu 10:

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following sentences

My father is in_______ of 30 engineers and 80 workers.

Xem đáp án » 18/07/2024 163

Câu 11:

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following sentences

________they arrived __________they were told to go back.

Xem đáp án » 22/07/2024 163

Câu 12:

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: “_______”

Xem đáp án » 18/07/2024 152

Câu 13:

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

Xem đáp án » 18/07/2024 152

Câu 14:

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following sentences

I believe nobody survived the plane crash_________

Xem đáp án » 20/07/2024 147

Câu 15:

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following sentences

Yuri Gagarin was the first person __________into space

Xem đáp án » 18/07/2024 147

Câu hỏi mới nhất

Xem thêm »
Xem thêm »