文勇的新托福黄金&ccedil

diversityatleastintemperatezonesmaximumdiversityisoft

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Unformatted text preview: tate’s electricity, enough to meet the residential needs of a city as large as San Francisco). In principle, all the power needs of the United States could be provided by exploiting the wind potential of just three states—North Dakota, South Dakota, and Texas. 1. Based on the information in paragraph 1, which of the following best explains the term wind farms? ○Farms using windmills to pump water ○Research centers exploring the uses of wind ○Types of power plant common in North Dakota ○Collections of wind turbines producing electric power 146 [email protected] 在在在在在在 www.liuwenyong.com 在在在在在在在在在在在在在在在,在在在在在在在在在在 Paragraph 2 在 Large wind farms can be built in six months to a year and then easily expanded as needed. With a moderate to fairly high net energy yield, these systems emit no heat­trapping carbon dioxide or other air pollutants and need no water for cooling; manufacturing them produces little water pollution. The land under wind turbines can be used for grazing cattle and other purposes, and leasing land for wind turbines can provide extra income for farmers and ranchers. 2. The word emit in the passage is closest in meaning to ○Use ○Require ○Release ○Destroy Paragraph 3: Wind power has a significant cost advantage over nuclear power and has become competitive with coal­fired power plants in many places. With new technological advances and mass production, projected cost declines should make wind power one of the world’s cheapest ways to produce electricity. In the long run, electricity from large wind farms in remote areas might be used to make hydrogen gas from water during periods when there is less than peak demand for electricity. The hydrogen gas could then be fed into a storage system and used to generate electricity when additional or backup power is needed. Paragraph 4: Wind power is most economical in areas with steady winds. In areas where the wind dies down, backup electricity from a utility company or from an energy storage system becomes necessary. Backup power could also be provided by linking wind farms with a solar cell, with conventional or pumped­storage h ydropower, or with efficient natural­gas­burning turbines. Some drawbacks to wind farms include visual pollution and noise, although these can be overcome by improving their design and locating them in isolated areas. 3. Based on the information in paragraph 3 and paragraph 4, what can be inferred about the states of North Dakota, South Dakota, and Texas mentioned at the end of paragraph 1? ○They rely largely on coal­fired power plants. ○They contain remote areas where the winds rarely die down. ○Over 1 percent of the electricity in these states is produced by wind farms. ○Wind farms in these states are being expanded to meet the power needs of the United States. 4. According to paragraph 3, which of the following is true about periods when the demand for electricity is relatively low? ○These periods are times when wind turbines are powered by hydrogen gas. ○These periods...
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This note was uploaded on 09/17/2013 for the course LANGUAGE 13DL208 taught by Professor Wang during the Fall '13 term at East China Normal University.

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