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Debate over the Use of Renewable EnergyAusubel of Rockefeller University in New York, US says the key renewable (可再生的) energy sources, including sun, wind and biofuels, would all require vast amounts of land if developed up to large scale production - unlike nuclear power. That land would be far better (51) alone, he says. Renewables look (52) when they are quite small. But if we start producing renewable energy on a large (53) , the fallout (结果) is going to be horrible.Ausubel draws his conclusions by analysing the amount of energy that renewables, natural gas and nuclei (原子核) can (54) in terms of power per square metre of land used. Moreover, he claims that (55) renewable energy use increases, this measure of efficiency will decrease as the best land for wind, biofuels, and solar power gets used up.Solar power is much more (56) than biofuel in terms of the area of land used, but it would still (57) 150 square kilometres of photovoltaic (光电的) cells to match the energy production of the 1000 MW nuclear plant. In another example, he says (58) the 2005 US electricity demand via wind power alone would need 780,000 square kilometres, an area the (59) of Texas.However, several experts are highly critical of Ausubel’s (60) . John Turner of the US government’s National Renewable Energy Laboratory says that even if the US got all of its (61) from solar energy, it would still need less than half the amount of land that has been paved over (62) highways. Further, it need not (63) up additional land. The US could get a quarter of its energy just from covering rooftops of existing buildings, he says.According to Turner, the same "dual use" also (64) to wind power. "The footprint for wind is only 5% of the land that it (65) . Farmers can still farm the land that the turbines are on." Turner says looking solely at land use is an oversimplification of the issue. 52（）
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（一） 某水坝工程可以满足各种功能要求的方案有A和B两个：A方案的建造费用为1000万元，每年的运行及维护费用为l50万元；B方案的建造费用为l500万元，每年的运行及维护费用为l00万元。两个方案的寿命期皆可以看作为无限年。设贷款的利率为5％。 根据题意，回答下述问题： B方案总费用的现值为（ ）万元。
49（）
第三篇：Sprained (扭伤) Ankle One of the most common injuries teenagers and adults experience is a sprained ankle. A sprain occurs when the ligaments(韧带) of a joint are twisted(扭伤) and possibly torn. Ligaments are bands of fibers that hold the bones of a joint in position. A sprain can occur from a sudden twisting at the joint, or a stretching or tearing of the fibers of the ligaments. The injured area usually swells(肿胀) and becomes black and blue. Stepping off the sidewalk at the wrong angle or having one foot land in a hole while walking or running can leave you rolling on the ground in pain with an ankle on fire! If you cannot walk without experiencing intense pain, you must seek medical help. If the pain is manageable, and you can walk, here are three words to help you remember how to treat yourself: ■ Elevate(抬高) ■ Cool ■ Bandage（打绷带） As soon as there is injury to that ligament, there will be a certain amount of bleeding under the skin. Once the blood pools around the damaged blood vessels, swelling occurs. The pressure from the swelling results in additional stress and tenderness to the region. In order to reduce the degree of swelling, lie down as soon as possible and keep the ankle elevated so that it is actually higher than your heart. Next, to reduce blood distribution and keep bleeding(流血) to minimum, apply a cold pack. After 20 minutes, take the pack off, wait half an hour, and then reapply. This can be several times a day for a total of three days. Never leave a cold pack on for more than 20 minutes at a time. Reducing the temperature in that area for an extended period of time signals the body to increase blood flow to raise the body temperature! Therefore, one accidentally triggers(引起) more blood distribution to the affected area by leaving a cold pack on for too long! Finally, bandage the angle. Be careful not to wind it too tightly; doing so can restrict blood flow and cause harm to the entire foot. The black—and—blue symptom of a sprain is due to（）
第一篇Centers of the Great European CitiesThe centers of the great cities of Europe are meeting places by tradition. People gather there to drink coffee and chat late into the night. A mixture of locals and tourists make for an exciting, metropolitan atmosphere.Squares, plazas (广场) and arcades (拱廊) form the heart of Europe’s cities.Venice in Italy has the Piazza San Marco - a beautiful square surrounded by shops, churches, restaurants and cafes. In Barcelona, Spain, La Bosqueria is a lively market with hundreds of stalls selling all kinds of goods. London’s Covent Garden is filled with fruit and vegetable stalls by day and musicians, acrobats (杂质演员) and artists by night. The government buildings at the center of many cities often are architecturally impressive. In London, they serve as a beautiful backdrop (背景) to the coffee tables that line the streets and the banks of the Thames.These vibrant (有活力的) hearts are the product of centuries of evolution, social historian Joel Garreau told US News and World Report recently. "The reason people think Venice is so great today is you don’t see all the mistakes," said Garreau. "Those have all been removed." Most European cities were laid out before the invention of the car, so bars, restaurants and cafes were near to people’s homes. Today, the focus of many Europeans’ life has moved away from the centers. They live in the suburbs and outskirts, driving to supermarkets to get their supplies. But on a continent where people treasure convention, there are still those who hold onto traditional ways, living and shopping locally. These people, together with tourists, provide the city centers with their reason for existence.Coffee culture plays a part in keeping these city centers flourishing. This is particularly true of Pads whose citizens are famous enthusiastic conversationalists. This skill is developed over many hours spent chatting over espressos (浓咖啡) and cigarettes.Religion also plays a role in developing sociable atmosphere. People in Roman Catholic countries used to visit the Church on an almost daily basis. Entire communities would gather in the same building and then move out to the markets, cafes and bars in the surrounding streets. An enormous example of this relationship between church and society is the Duomo. The huge marble cathedral in Florence, Italy is surrounded by bakeries and coffee shops, and caters not only to the tourist crowds, but also the local community. What are Parisians famous for（）
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