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Passage 2 When Jules Verne wrote Journey to the Center of the Earth in 1864, there were many conflicting theories about the nature of the Earth’ s interior. Some geologists thought that it contained a highly compressed ball of incandescent gas, while others suspected that it consisted of separate shells, each made of different materials. Today well over a century later, there is little direct evidence of what lies beneath our feet. Most of our knowledge of the Earth’ s interior comes not from mines or boreholes, but from the study of seismic waves--powerful pulses of energy released by earthquakes. The way that seismic waves travel shows that the Earth’ s interior is far from uniform. The continents and the seabed are formed by the crust--a thin sphere of relatively light, solid rock. Beneath the crust lies the mantle, a different layer that extends approximately halfway to the Earth’ s center. There the rock is the subject of a battle between increasing heat and growing pressure. In its high levels, the mantle is relatively cool; at greater depths, high temperatures make the rock behave more like a liquid than a solid. Deeper still, the pressure is even more intense, preventing the rock from melting in spite of a higher temperature. Beyond a depth of around 2,900 kilometers, a great change takes place and the mantle gives way to the core. Some seismic waves cannot pass through the core and others are bent by it. From this and other evidence, geologists conclude that the outer core is probably liquid, with a solid center. It is almost certainly made of iron, mixed with smaller amounts of other elements such as nickel. The conditions in the Earth’ s core make it a far more alien world than space. Its solid iron heart is subjected to unimaginable pressure and has a temperature of about 9,000°F. Although scientists can speculate about its nature, neither humans nor machines will ever be able to visit it. The phrase "gives way to" in the paragraph 4 is closest in meaning to ______ .
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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.
已知：某公司2010年第1～3月实际销售额分别为95000万元、90000万元和102500万元，预计4月份销售额为100000万元。每月销售收入中有60%能于当月收现，30%于次月收现，10%于第三个月收讫，不存在坏账。假定该公司销售的产品在流通环节只需缴纳消费税，税率为10%，并于当月以现金缴纳。该公司3月末现金余额为200万元，应付账款余额为12500万元(需在4月份付清)，不存在其他应收应付款项。 4月份有关项目预计资料如下：采购材料20000万元(当月付款70%)；工资及其他支出21000万元(用现金支付)；制造费用20000万元(其中折旧费等非付现费用为10000万元)；营业费用和管理费用2500万元(用现金支付)；预交所得税4750万元；购买设备30000万元(用现金支付)。现金不足时，通过向银行借款解决。4月末现金余额要求不低于250万元。 要求：根据上述资料，计算该4公司月份的下列预算指标： 4月末应收账款余额。
Part A For questions 1-5, you will hear a passage. Listen and answer the questions with the information you’ ve heard. Write not more than 3 words in each blank. You will hear the recording twice. You now have 25 seconds to read the questions below. There’ s more to Niagara Falls than ______ .
Passage 4 For many years, Antarctica was thought to be only an archipelago whose islands were tied together above sea level by ice. It was thought to be made up of two small subcontinents--East Antarctica, the larger, and West Antarctica, containing the Antarctic Peninsula. The two continents were supposed to be separated by a large trough, below sea level, that connected the Ross and Weddell Seas. Geophysical studies have now revealed a fairly complete picture of the Antarctic landform below its ice cover. We know now that West Antarctica is connected to the main part of the continent by a chain of mountains well above sea level, though largely buried by ice and snow. The bedrock of much of East Antarctica appears to be above sea level. Whether mineral wealth lies hidden by the vast ice sheets is unknown. No more than 2 percent of the continent is actual rock outcrop and much of this small and probably unrepresentative sample has yet to be visited by geologists. Certainly no deposits rich enough to be economically useful have been found. Geologists now know that the ice-buried rocks of the Antarctic are similar to rocks of the other continents of the world. Minor amounts of potentially valuable minerals have been reported. The presence of petroleum has been speculated upon by several geologists, but none has yet been found. Low-grade deposits of coal are widespread, especially in the Transantarctic Mountains, but there has been no attempt at exploitation. Even if rich mineral deposits were to be found in Antarctica, the cost of removal from this remote and inhospitable land would be exorbitant. Interpretation of continental structure is an important objective of any extensive geologic investigation. Yet except for the earth’ s ocean basins, no area the size of Antarctica is so geologically unknown. With 98 percent of the continent covered by ice, it is extremely difficult to decipher the continent’ s general structure. Geologists determine geologic structure by studying rock outcrops, and many of these are small and widely separated. No outcrops are known in the vast interior of East Antarctica. Working out the continental structure of Antarctica is analogous to learning that of the entire United States from studies of a few scattered counties in California and mountain ranges scattered at irregular intervals across the country. In Antarctica, petroleum ______ .
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