Cách pha loãng H₂SO₄ đặc an toàn là :

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: Which of the following describes the sequence of color changes that lantana blossom undergo?         

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: The word “haphazard” is closest in meaning to which of the following?             

Read the following passage and choose the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:

Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects. For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar. In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Question: The passage implies that insects would be most attracted to lantana blossoms_______         

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:

During the 19th century, women in the U.S organized and participated in a large number of reform movements, including movements to reorganize the prison system, improve education, ban the sale of alcohol, and most importantly to free slaves. Some women saw similarities in the social status of women and slaves. Women like Elizabeth Cady Stanton and Lucy Stone were feminists and abolitionists who supported the rights of both women and blacks. A number of male abolitionists, including William Lloyd Garrison and Wendell Phillips also supported the rights of women to speak and participate equally with men in anti-slavery activities. Probably more than any other movement, abolitionism offered women a previously denied entry into politics. They became involved primarily in order to better their living conditions and the conditions of others. When the Civil war ended in 1865, the 14th, and 15th, Amendments to the Constitution adopted in 1868 and 1870 granted citizenship and suffrage to blacks but not to women. Discouraged but resolved, feminists influenced more and more women to demand the right to vote. In 1869, the Wyoming Territory had yielded to demands by feminists, but eastern states resisted more stubbornly than ever before. A woman's suffrage bill had been presented to every Congress since 1878 but it continually failed to pass until 1920, when the 19th Amendment granted women the right to vote.

Question 39: What is the topic of 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:

During the 19th century, women in the U.S organized and participated in a large number of reform movements, including movements to reorganize the prison system, improve education, ban the sale of alcohol, and most importantly to free slaves. Some women saw similarities in the social status of women and slaves. Women like Elizabeth Cady Stanton and Lucy Stone were feminists and abolitionists who supported the rights of both women and blacks. A number of male abolitionists, including William Lloyd Garrison and Wendell Phillips also supported the rights of women to speak and participate equally with men in anti-slavery activities. Probably more than any other movement, abolitionism offered women a previously denied entry into politics. They became involved primarily in order to better their living conditions and the conditions of others. When the Civil war ended in 1865, the 14th, and 15th, Amendments to the Constitution adopted in 1868 and 1870 granted citizenship and suffrage to blacks but not to women. Discouraged but resolved, feminists influenced more and more women to demand the right to vote. In 1869, the Wyoming Territory had yielded to demands by feminists, but eastern states resisted more stubbornly than ever before. A woman's suffrage bill had been presented to every Congress since 1878 but it continually failed to pass until 1920, when the 19th Amendment granted women the right to vote.

Question 38: What is not among the reformation movements of women?             

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:

During the 19th century, women in the U.S organized and participated in a large number of reform movements, including movements to reorganize the prison system, improve education, ban the sale of alcohol, and most importantly to free slaves. Some women saw similarities in the social status of women and slaves. Women like Elizabeth Cady Stanton and Lucy Stone were feminists and abolitionists who supported the rights of both women and blacks. A number of male abolitionists, including William Lloyd Garrison and Wendell Phillips also supported the rights of women to speak and participate equally with men in anti-slavery activities. Probably more than any other movement, abolitionism offered women a previously denied entry into politics. They became involved primarily in order to better their living conditions and the conditions of others. When the Civil war ended in 1865, the 14th, and 15th, Amendments to the Constitution adopted in 1868 and 1870 granted citizenship and suffrage to blacks but not to women. Discouraged but resolved, feminists influenced more and more women to demand the right to vote. In 1869, the Wyoming Territory had yielded to demands by feminists, but eastern states resisted more stubbornly than ever before. A woman's suffrage bill had been presented to every Congress since 1878 but it continually failed to pass until 1920, when the 19th Amendment granted women the right to vote.

 Question 37: What cannot be inferred from 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:

During the 19th century, women in the U.S organized and participated in a large number of reform movements, including movements to reorganize the prison system, improve education, ban the sale of alcohol, and most importantly to free slaves. Some women saw similarities in the social status of women and slaves. Women like Elizabeth Cady Stanton and Lucy Stone were feminists and abolitionists who supported the rights of both women and blacks. A number of male abolitionists, including William Lloyd Garrison and Wendell Phillips also supported the rights of women to speak and participate equally with men in anti-slavery activities. Probably more than any other movement, abolitionism offered women a previously denied entry into politics. They became involved primarily in order to better their living conditions and the conditions of others. When the Civil war ended in 1865, the 14th, and 15th, Amendments to the Constitution adopted in 1868 and 1870 granted citizenship and suffrage to blacks but not to women. Discouraged but resolved, feminists influenced more and more women to demand the right to vote. In 1869, the Wyoming Territory had yielded to demands by feminists, but eastern states resisted more stubbornly than ever before. A woman's suffrage bill had been presented to every Congress since 1878 but it continually failed to pass until 1920, when the 19th Amendment granted women the right to vote.

Question 36: What does the 19th Amendment guarantee?         

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:

Most languages have several levels of vocabulary that may be used by the same speakers. In English, at least three have been identified and described. Standard usage includes those words and expressions understood, used, and accepted by a majority of the speakers of a language in any situation regardless of the level of formality. As such, these words and expressions are well defined and listed in standard dictionaries. Colloquialisms, on the other hand, are familiar words and idioms that are understood by almost all speakers of a language and used in informal speech or writing, but not considered acceptable for more formal situations. Almost all idiomatic expressions are colloquial language. Slang, however, refers to words and expressions understood by a large number of speakers but not accepted as appropriate formal usage by the majority. Colloquial expressions and even slang may be found in standard dictionaries but will be so identified. Both colloquial usage and slang are more common in speech than in writing. Colloquial speech often passes into standard speech. Some slang also passes into standard speech, but other slang expressions enjoy momentary popularity followed by obscurity. In some cases, the majority never accepts certain slang phrases but nevertheless retains them in their collective memories. Every generation seems to require its own set of words to describe familiar objects and events. It has been pointed out by a number of linguists that three cultural conditions are necessary for the creation of a large body of slang expressions. First, the introduction and acceptance of new objects and situations in the society; second, a diverse population with a large number of subgroups; third, association among the subgroups and the majority population. Finally, it is worth nothing that the terms “standard”, “colloquial”, and “slang” exist only as abstract levels for scholars who study language. Only a tiny number of the speakers of any language will be aware that they are using colloquial or slang expressions. Most speakers of English will, during appropriate situations, select and use all three types of expressioins.

Question 43: How is slang defined by the author?         

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:

Most languages have several levels of vocabulary that may be used by the same speakers. In English, at least three have been identified and described. Standard usage includes those words and expressions understood, used, and accepted by a majority of the speakers of a language in any situation regardless of the level of formality. As such, these words and expressions are well defined and listed in standard dictionaries. Colloquialisms, on the other hand, are familiar words and idioms that are understood by almost all speakers of a language and used in informal speech or writing, but not considered acceptable for more formal situations. Almost all idiomatic expressions are colloquial language. Slang, however, refers to words and expressions understood by a large number of speakers but not accepted as appropriate formal usage by the majority. Colloquial expressions and even slang may be found in standard dictionaries but will be so identified. Both colloquial usage and slang are more common in speech than in writing. Colloquial speech often passes into standard speech. Some slang also passes into standard speech, but other slang expressions enjoy momentary popularity followed by obscurity. In some cases, the majority never accepts certain slang phrases but nevertheless retains them in their collective memories. Every generation seems to require its own set of words to describe familiar objects and events. It has been pointed out by a number of linguists that three cultural conditions are necessary for the creation of a large body of slang expressions. First, the introduction and acceptance of new objects and situations in the society; second, a diverse population with a large number of subgroups; third, association among the subgroups and the majority population. Finally, it is worth nothing that the terms “standard”, “colloquial”, and “slang” exist only as abstract levels for scholars who study language. Only a tiny number of the speakers of any language will be aware that they are using colloquial or slang expressions. Most speakers of English will, during appropriate situations, select and use all three types of expressioins.

Question 42: The word “them” refers to .....         

Có bao nhiêu cách xếp bạn A, B, C, D, E, F vào một ghế dài sao cho bạn A, F ngồi ở đầu ghế?