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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 from 35 to 42. Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants. The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them. In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms. The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season. Which of the following is NOT given as an advantage of using biological agents over chemical herbicides? 
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 from 35 to 42. Humans have struggled against weeds since the beginnings of agriculture. Marring our gardens is one of the milder effects of weeds - any plants that thrive where they are unwanted. They clog waterways, destroy wildlife habitats, and impede farming. Their spread eliminates grazing areas and accounts for one-third of all crop loss. They compete for sunlight, nutrients, and water with useful plants. The global need for weed control had been answered mainly by the chemical industry. Its herbicides are effective and sometimes necessary, but some pose serious problems, particularly if misused. Toxic compounds threaten animal and public health when they accumulate in food plants, groundwater, and drinking water. They also harm workers who apply them. In recent years, the chemical industry has introduced several herbicides that are more ecologically sound. Yet new chemicals alone cannot solve the world's weed problems. Hence, scientists are exploring the innate weed-killing powers of living organisms, primarily insects and microorganisms. The biological agents now in use are environmentally benign and are harmless to humans. They can be chosen for their ability to attack selected targets and leave crops and other plants untouched. In contrast, some of the most effective chemicals kill virtually all the plants they come in contact with, sparing only those that are naturally resistant or have been genetically modified for resistance. Furthermore, a number of biological agents can be administered only once, after which no added applications are needed. Chemicals typically must be used several times per growing season. Which of the following statements about the use of chemical agents as herbicides would the author most likely agree? 
  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 from 43 to 50.  Plants and animals will find it difficult to escape from or adjust to the effects of global warming. Scientists have already observed shifts in the lifecycles of many plants and animals, such as flowers blooming earlier and birds hatching earlier in the spring. Many species have begun shifting where they live or their annual migration patterns due to warmer temperatures. With further warming, animals will tend to migrate toward the poles and up mountainsides toward higher elevations. Plants will also attempt to shift their ranges, seeking new areas as old habitats grow too warm. In many places, however, human development will prevent these shifts. Species that find cities or farmland blocking their way north or south may become extinct. Species living in unique ecosystems, such as those found in polar and mountaintop regions, are especially at risk because migration to new habitats is not possible. For example, polar bears and marine mammals in the Arctic are already threatened by dwindling sea ice but have nowhere farther north to go. Projecting species extinction due to global warming is extremely difficult. Some scientists have estimated that 20 to 50 percent of species could be committed to extinction with 2 to 3 Celsius degrees of further warming. The rate of warming, not just the magnitude, is extremely important for plants and animals. Some species and even entire ecosystems, such as certain types of forest, may not be able to adjust quickly enough and may disappear. Ocean ecosystems, especially fragile ones like coral reefs, will also be affected by global warming. Warmer ocean temperatures can cause coral to “bleach”, a state which if prolonged will lead to the death of the coral. Scientists estimate that even 1 Celsius degree of additional warming could lead to widespread bleaching and death of coral reefs around the world. Also, increasing carbon dioxide in the atmosphere enters the ocean and increases the acidity of ocean waters. This acidification further stresses ocean ecosystems. According to the passage, if some species are not able to adjust quickly to warmer temperatures, ______. 
  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 from 43 to 50.  Plants and animals will find it difficult to escape from or adjust to the effects of global warming. Scientists have already observed shifts in the lifecycles of many plants and animals, such as flowers blooming earlier and birds hatching earlier in the spring. Many species have begun shifting where they live or their annual migration patterns due to warmer temperatures. With further warming, animals will tend to migrate toward the poles and up mountainsides toward higher elevations. Plants will also attempt to shift their ranges, seeking new areas as old habitats grow too warm. In many places, however, human development will prevent these shifts. Species that find cities or farmland blocking their way north or south may become extinct. Species living in unique ecosystems, such as those found in polar and mountaintop regions, are especially at risk because migration to new habitats is not possible. For example, polar bears and marine mammals in the Arctic are already threatened by dwindling sea ice but have nowhere farther north to go. Projecting species extinction due to global warming is extremely difficult. Some scientists have estimated that 20 to 50 percent of species could be committed to extinction with 2 to 3 Celsius degrees of further warming. The rate of warming, not just the magnitude, is extremely important for plants and animals. Some species and even entire ecosystems, such as certain types of forest, may not be able to adjust quickly enough and may disappear. Ocean ecosystems, especially fragile ones like coral reefs, will also be affected by global warming. Warmer ocean temperatures can cause coral to “bleach”, a state which if prolonged will lead to the death of the coral. Scientists estimate that even 1 Celsius degree of additional warming could lead to widespread bleaching and death of coral reefs around the world. Also, increasing carbon dioxide in the atmosphere enters the ocean and increases the acidity of ocean waters. This acidification further stresses ocean ecosystems. The bleaching of coral reefs as mentioned in paragraph 4 indicates ______. 
  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 from 43 to 50.  Plants and animals will find it difficult to escape from or adjust to the effects of global warming. Scientists have already observed shifts in the lifecycles of many plants and animals, such as flowers blooming earlier and birds hatching earlier in the spring. Many species have begun shifting where they live or their annual migration patterns due to warmer temperatures. With further warming, animals will tend to migrate toward the poles and up mountainsides toward higher elevations. Plants will also attempt to shift their ranges, seeking new areas as old habitats grow too warm. In many places, however, human development will prevent these shifts. Species that find cities or farmland blocking their way north or south may become extinct. Species living in unique ecosystems, such as those found in polar and mountaintop regions, are especially at risk because migration to new habitats is not possible. For example, polar bears and marine mammals in the Arctic are already threatened by dwindling sea ice but have nowhere farther north to go. Projecting species extinction due to global warming is extremely difficult. Some scientists have estimated that 20 to 50 percent of species could be committed to extinction with 2 to 3 Celsius degrees of further warming. The rate of warming, not just the magnitude, is extremely important for plants and animals. Some species and even entire ecosystems, such as certain types of forest, may not be able to adjust quickly enough and may disappear. Ocean ecosystems, especially fragile ones like coral reefs, will also be affected by global warming. Warmer ocean temperatures can cause coral to “bleach”, a state which if prolonged will lead to the death of the coral. Scientists estimate that even 1 Celsius degree of additional warming could lead to widespread bleaching and death of coral reefs around the world. Also, increasing carbon dioxide in the atmosphere enters the ocean and increases the acidity of ocean waters. This acidification further stresses ocean ecosystems. It is mentioned in the passage that if the global temperature rose by 2 or 3 Celsius degrees, ______. 
  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 from 43 to 50.  Plants and animals will find it difficult to escape from or adjust to the effects of global warming. Scientists have already observed shifts in the lifecycles of many plants and animals, such as flowers blooming earlier and birds hatching earlier in the spring. Many species have begun shifting where they live or their annual migration patterns due to warmer temperatures. With further warming, animals will tend to migrate toward the poles and up mountainsides toward higher elevations. Plants will also attempt to shift their ranges, seeking new areas as old habitats grow too warm. In many places, however, human development will prevent these shifts. Species that find cities or farmland blocking their way north or south may become extinct. Species living in unique ecosystems, such as those found in polar and mountaintop regions, are especially at risk because migration to new habitats is not possible. For example, polar bears and marine mammals in the Arctic are already threatened by dwindling sea ice but have nowhere farther north to go. Projecting species extinction due to global warming is extremely difficult. Some scientists have estimated that 20 to 50 percent of species could be committed to extinction with 2 to 3 Celsius degrees of further warming. The rate of warming, not just the magnitude, is extremely important for plants and animals. Some species and even entire ecosystems, such as certain types of forest, may not be able to adjust quickly enough and may disappear. Ocean ecosystems, especially fragile ones like coral reefs, will also be affected by global warming. Warmer ocean temperatures can cause coral to “bleach”, a state which if prolonged will lead to the death of the coral. Scientists estimate that even 1 Celsius degree of additional warming could lead to widespread bleaching and death of coral reefs around the world. Also, increasing carbon dioxide in the atmosphere enters the ocean and increases the acidity of ocean waters. This acidification further stresses ocean ecosystems. The pronoun “those” in paragraph 2 refers to ______. 
Clara Barton became known as "The Angel of the Battlefield" during the American Civil War. Born in Oxford, Massachusetts in 1821, Clara Barton's interest in helping soldiers on the battlefield began when she was told army stories from her father. Another event that influenced her decision to help soldiers was an accident her brother had. His injuries were cared for by Barton for 2 years. At the time, she was only Il years old. Barton began teaching school at the age of 15. She taught for 18 years before she moved to Washington, D.C. in 1854. The civil war broke out 6 years later. Immediately, Barton started war service by helping the soldiers with their needs. At the battle of Bull Run, Clara Barton received permission from the government to take care of the sick and hurt. Barton did this with great empathy and kindness. She acknowledged each soldier as a person. Her endurance and courage on the battlefield were admired by many. When the war ended in 1865, she used 4 years of her life to assist the government in searching for soldiers who were missing during the war. The search for missing soldiers and years of hard work made her feeble physically. In 1869, her doctors recommended a trip to Europe for a rest. While she was on vacation, she became involved with the International Red Cross, an organization set up by the Geneva Convention in 1864. Clara Barton realized that the Red Cross would be a big help to the United States. After she returned to the United States, she worked very hard to create an American Red Cross. She talked to government leaders and let American people know about the Red Cross. In 1881, the National Society of the Red Cross was finally established with its headquarters in Washington, D.C. Clara Barton managed its activities for 23 years. Barton never let her age stop her from helping people. At the age of 79, she helped flood victims in Galveston, Texas. Barton finally resigned from the Red Cross in 1904. She was 92 years old and had truly earned her title "The Angel of the Battlefield". What does the author mention about the American Red Cross?