题目内容
In 1971 there were about 3,700 million people in the world. If the population were (21) evenly over the earth’ s surface there would be about 50 people to the square mile; but there are vast areas of desert and mountain and tropical forest (22) are uninhabited, (23) at the other (24) , in the great cities millions may live within a few square miles. (25) of the world’ s population is concentrated on only a small (26) of the earth’ s land surface, in the rich valleys and (27) plains, because people up to the present time have (28) to congregate in place where the climate and soil make it easy to grow food and obtain shelter. A (29) world population and the discoveries of science (30) this pattern of distribution in the future. As men slowly learn to master diseases, control floods, prevent famines, and stop wars, fewer people die every year; and in (31) the population of the world is steadily (32) . When numbers (33) , the extra mouths must be fed. New lands must be brought (34) cultivation, or land already (35) , made to yield larger crops. In some areas the accessible land is largely so intensively cultivated (36) it will be difficult to make it (37) more food. in some areas the population is so dense that the land is divided into. units (38) tiny to allow for much improvement in farming methods. (39) a large part of this farming population drawn (40) into industrial occupations, the land might be farmed much more productively by modern methods.
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资料1：甲企业为生产应税消费品的企业，销售利润率为20%，适用的增值税税率为17%，材料成本占总成本的百分比为60%。 资料2：该企业生产所使用的材料都是在当期内采购的，适用的消费税税率为10%，城市维护建设税税率为7%，教育费附加的征收率为3%。 资料3：2009年的含税销售收入为2340万元，2010年甲企业预计的含税销售收入为2925万元，预计其他业务收入为100万元(需要交纳营业税，税率为5%)，预交所得税200万元，直接计入管理费用的印花税为4万元。 资料4：当年采购的材料，有60%在当年付款，其余的40%在下年付款。 要求： 计算2010年的现购材料现金支出。
Passage 1 Humans are forever forgetting that they can’ t control nature. Exactly 20 years ago, a Time magazine cover story announced that scientists are on the verge of being able to predict the time, place and even the size of earthquakes. "The people of quake-ravaged Kobe learned last week how wrong that assertion was." None of the methods conceived two decades ago has yet to discover a uniform warning signal that preceded all quakes, let alone any sign that would tell whether the coming tremor is mild or a killer. Earthquake formation can be triggered by many factors, says Hiroo Kanamori, a seismologist at the California Institute of Technology. So, finding one all-purpose warning sign is impossible. One reason: Quakes start deep in the earth, so scientists can’ t study them directly. If a quake precursor were found, it would still be impossible to warn humans in advance of all dangerous quakes. Places like Japan and California are riddled with hundreds, if not thousands, of minor faults. Prediction would be less important if scientists could easily build structures to withstand tremors. While seismic engineering has improved dramatically in the past 10 to 15 years, every new quake reveals unexpected weaknesses in "quake-resistant" structures, says Terry Tullis, a geophysicist at Brown University. In Kobe, for example, a highway that opened only last year was damaged. In the Northridge earthquake, on the other hand, well-built structures generally did not collapse. A recent report in science adds yet more anxiety about life on the faulty lines. Researchers ran computer simulations to see how quake-resistant buildings would fare in a moderate-size tremor, taking into account that much of a quakes energy travels in a large "pulse" of focused shaking. The results: Both steel-frame buildings and buildings that sit on insulating rubber pads suffered severe damage. More research will help experts design stronger structures and possibly find quake precursors. But it is still a certainty that the next earthquakes will prove once again that every fault cannot be monitored and every highway cannot be completely quake-proofed. One of the chief difficulties in accurate earthquake warning is that ______ .
Passage 3 Most scientists blame people, at least in part, for global warming. Now, some researchers say people may be partly to blame for the cooling of Antarctica as well. While average global temperatures have risen about one degree Fahrenheit over the past century, Antarctica over all appears to have cooled slightly in the past few decades. That has been puzzling, because the polar regions are thought to be more sensitive to warming trends than the rest of the globe. Even more puzzling, a small portion of Antarctica--the peninsula that stretches north toward South America--defies the cooling trend. It has been warming very rapidly, about five degrees over the past 50 years, 10 times the global average. Writing in today’ s issue of the journal Science, Dr. David Thompson, a professor of atmospheric science at Colorado State University, and Dr. Susan Solomon, a senior scientist at the National Oceanic and Atmospheric Administration in Boulder, Colo., argue that the ozone hole, which has opened up each spring over Antarctica in recent years, may help explain both contradictory trends. A vortex of winds continually blows around Antarctica, tending to trap cold air at the South Pole. In the new paper, Dr. Thompson and Dr. Solomon show that the winds have strengthened in the past few decades, keeping the cold air even more confined. The peninsula, which lies outside the wind vortex, escapes the cooling effect, the scientists said. They say the ozone hole may be the cause of the stronger winds. Close to the ground, ozone, a molecule consisting of three oxygen atoms, forms a large and unhealthy component of smog. High in the atmosphere, however, nature occurring ozone is essential for life, blocking ultraviolet rays that would fatally mangle DNA. However, fewer ozone molecules mean the atmosphere absorbs less ultraviolet radiation. Instead of warming the air, the rays bounce off the snow and ice of Antarctica and reflect back into space. Scientists already knew that the ozone hole had cooled the upper atmosphere. Dr. Thompson and Dr. Solomon show that the troposphere, the lowest six miles of the atmosphere, has also cooled. "It’ s a lot of food for thought in there," said Dr. John Walsh, a professor of atmospheric science at the University of Illinois and an author of a paper in Science in January that indicated Antarctica was cooling. He noted that the ozone hole was usually largest in November or December, but that the greatest cooling had been about six months later. We can infer that in Antarctica the coldest period is ______ .
In 1971 there were about 3,700 million people in the world. If the population were (21) evenly over the earth’ s surface there would be about 50 people to the square mile; but there are vast areas of desert and mountain and tropical forest (22) are uninhabited, (23) at the other (24) , in the great cities millions may live within a few square miles. (25) of the world’ s population is concentrated on only a small (26) of the earth’ s land surface, in the rich valleys and (27) plains, because people up to the present time have (28) to congregate in place where the climate and soil make it easy to grow food and obtain shelter. A (29) world population and the discoveries of science (30) this pattern of distribution in the future. As men slowly learn to master diseases, control floods, prevent famines, and stop wars, fewer people die every year; and in (31) the population of the world is steadily (32) . When numbers (33) , the extra mouths must be fed. New lands must be brought (34) cultivation, or land already (35) , made to yield larger crops. In some areas the accessible land is largely so intensively cultivated (36) it will be difficult to make it (37) more food. in some areas the population is so dense that the land is divided into. units (38) tiny to allow for much improvement in farming methods. (39) a large part of this farming population drawn (40) into industrial occupations, the land might be farmed much more productively by modern methods.
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