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Questions 17 to 20 are based.on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions. Now, listen to the passage. Through the use of computers, all of the following can be done EXCEPT ______
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Children’s stories such as" Little Red Riding Hood" and" The Three Little Pigs" have depicted wolves as frightening animals. In reality, these animals are social, nurturing creatures. They often spend the better part of their day playing with and tending to their young. There are two recognized species of wolves: the gray wolf and the red wolf. The grey wolf, is the largest member of the wolf family. The grey wolf had one of the widest distributions of all mammals on the planet. It once roamed North America, Europe, and Asia, but years of persecution have reduced its numbers significantly, especially in Europe. In Alaska, the northwest territories, and the former Soviet Union, the grey wolf has a thriving population. In the Northwest United States, however, the grey wolf is almost extinct, with a population of perhaps 30. Farther south in the United States the grey has disappeared completely. In Mexico, researchers estimated that fewer than 10 greys survive. The grey wolf became extinct in England about 1486 ;it disappeared from Scotland in 1743 and from Ireland in 1770. Once grey wolf could be found in many parts of the earth.
SECTION A CONVERSATIONS In this section you will hear several conversations. Listen carefully and then answer the questions that follow. Questions 1 to 3 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions. Now, listen to the conversation. How much does the woman finally pay for what she wants to get
TEXT A Mind Your Calories or Your Waistline Cutting back the calories may do more than whittle your waistline; it could protect your brain from the effects of aging. A new study suggests that calorie restriction can help slow the normal process of cell death that happens with age. Researchers say the body naturally goes through a process known as apoptosis, or cell death, to destroy old cells so new ones can be made, and many factors can alter this process. Age-related diseases, such as Alzheimer’s and Parkinson’s, cause a higher-than-normal loss of cells in the brain, which can lead to loss of function. Previous studies have suggested that calorie restriction can boost life span and mental capacity. That prompted researchers to look at whether cutting calories might also play a role in protecting aging brain cells. They compared levels of proteins indicating brain cell death in two groups of rats. One group was given unrestricted access to food and water throughout their lives. The other was given 40% fewer calories (but still adequate nourishment) than the unrestricted group. They found that the levels of these proteins increased with normal aging in the rats fed unrestricted diets. The rats given a restricted diet did not have an increase in the levels of these proteins. Another protein thought to protect from cell death dropped by 60% in the well-fed rats, but it actually increased over time in the calorie-restricted rats. Finally, DNA fragmentation, a third indicator of cell death, more than doubled in the unrestricted rats with age, but this increase was 36% less in the calorie-restricted rats. Although the results are promising, researchers say more study is needed to completely understand the processes that lead to cell death and the role nutrition plays in that process. Meanwhile, they say, their study provides yet another reason to watch what you eat. "We’re not going to do it right away to improve our memories; we’re going to do it probably in general for the first reasons, which would be to prevent cardiovascular disease and cancer," says Christian Leeuwenburgh at the University of Florida. The main purpose of these researchers is ______
Questions 27 and 28 are based on the following news. At the end of the news item, you will be given 10 seconds to answer the questions. Now, listen to the news. It was obvious that the team ______
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