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One billion people in the world are short of water. How can this problem be solved Some suggestions have been to desalinate ocean water or to build enormous water pipelines from areas where water is abundant. (Suggestions such as these prove extremely expensive when they are actually used. ) One possibility that scientists are considering is pulling icebergs from either the North Pole or the South Pole to parts of the world with a water shortage. Although many questions must be answered before such a project could be tried, moving icebergs seems a reasonable possibility in the future.Engineers, mathematicians, and glaciologists from a dozen countries have been considering the iceberg as a future source of water. Saudi Arabia is particularly interested in this project because it has a great water shortage. Scientists estimate that it would take 128 days to transport a large iceberg (about 1/2 square mile) to Saudi Arabia. Yet the iceberg would be completely melted by the 104th day. Therefore, insulation would be essential, but how to insulate the iceberg remains an unsolved problem.The problems in transporting an iceberg are numerous. The first problem is choosing the iceberg to pull. The icebergs that form in the North Pole are quite difficult to handle because of their shape. Only a small portion extends above the water — most of the iceberg is below the surface, which would make it difficult to pull. South Pole icebergs, on the other hand, are flat and float like table tops. Thus they would be much easier to move.How can a 200-million-ton iceberg be moved No ship is strong enough to pull such enormous weight through the water. Perhaps several ships could be used. Attaching ropes to an iceberg this size is also an enormous problem. Engineers think that large nails or long metal rods could be driven into the ice. What would happen if the iceberg splits into several pieces during the pulling Even if an iceberg with very few cracks were chosen, how could it be pulled through stormy waters Furthermore, once the iceberg reached its destination, very few ports would be deep enough to store it.All of these problems must be solved before icebergs can become a reasonable source of water. Yet scientists estimate that it will be possible to transport them in the near future. Each year, enough icebergs form to supply the whole world with fresh water for a full year. In addition, icebergs are free and nonpolluting. As a solution to the world’s water problems, icebergs may be a workable possibility. What’s the writer’s attitude towards transporting icebergs（）
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It doesn’t take an Einstein to recognize that Albert Einstein’s brain was very different from yours and mine. The gray matter housed inside that shaggy head managed to revolutionize our concepts of time, space, motion — the very foundations of physical reality — not just once but several times during his astonishing career. Yet while there clearly had to be something remarkable about Einstein’s brain, the pathologist who removed it from the great physicist’s skull after his death reported that the organ was, to all appearances, well within the normal range — no bigger or heavier than anyone else’s.But a new analysis of Einstein’s brain by Canadian scientists reveals that it has some distinctive physical characteristics after all. A portion of the brain that governs mathematical ability and spatial reasoning — two key ingredients to the sort of thinking Einstein did best — was significantly larger than average. Its cells may have been more closely connected, which could have allowed them to work together more effectively. While the case is far from proven, it’s a fascinating discovery.What they found was that while the overall size of Einstein’s brain was about average, a region called the inferior parietal lobe (顶骨下叶) was about 15% wider than normal. "visuaspatial (视觉空间) cognition, mathematical thought and imagery of movement, " write Witelson and her co-authors, "are strongly dependent on this region. " And as it happens, Einstein’s impressive insights tended to come from visual images he conjured up intuitively, and were then translated into the language of mathematics ( the theory of special relativity, for example, was triggered by his musing on what it would be like to ride through space on a beam of light).Not only was Einstein’s inferior parietal region unusually bulky, the scientists found, but a feature called the Sylvian fissure (大脑外侧裂) was much smaller than average. Without the groove that normally slices through the tissue, the brain cells were parked close together, permitting more interconnections — which in principle can permit more cross-referencing of information and ideas, leading to great leaps of insight.That’s the idea, anyway. But while it’s quite plausible according to current neurological theory, that doesn’t necessarily make it true. We know Einstein was a genius, and we now know that his brain was physically different from the average. But none of this proves a cause- and-effect relationship. "What you really need, " says Dr. Francine Benes, director of the Structural Neuroscience Laboratory at Meclean Hospital, "is to look at the brains of a number of mathematical geniuses to see if the same abnormalities are present. "Even if they are, it’s possible that the bulked-up brains are result of strenuous mental exercise, not an inherent feature that makes genius possible. Bottom line: we still don’t know whether Einstein was born with an extraordinary mind or whether he earned it, one brilliant idea at a time. The passage is mainly about（）
In Japan, most people still feel that a woman’s place is in the home; and most women willingly accept their (31) role as wife, leaving the business of making a living (32) their husbands. For those who do want a (33) of their own, opportunities are limited, and working women usually have to (34) for low wages, fewer promotions, less responsible (35) .In America, on the other hand, most women, (36) wives and mothers, work most of their times. But (37) few have had real careers. As in Japan, most fields are (38) by men and opportunities for women have been (39) , salaries low, chances for advancement (40) American women work mainly because they (41) ; in these days of inflation and luxury living, (42) income per family is simply not enough to (43) . So American women actually have two jobs: one nine-to-five position outside the home, and (44) round-the-clock in the home job (45) wife, housemaid, cook and nurse.One of the main goals of the modern women’s liberation movement, which started (46) , was to eliminate sex discrimination in the work force, and to (47) careers for women that were previously (48) for men. And though there is still a long way to (49) , a lot of progress has been (50) . （49）（）
Much of the language used to describe monetary policy, such as "steering the economy to a soft landing" or "a touch on the brakes", makes it sound like a precise science. Nothing could be further from the truth. The link between interest rates and inflation is uncertain. And there are long, variable lags before policy changes have any effect on the economy. Hence the analogy that likens the conduct of monetary policy to driving a car with a blackened windscreen, a cracked rear-view mirror and a faulty steering wheel.Given all these disadvantages, central bankers seem to have had much to boast about of late. Average inflation in the big seven industrial economies fell to a mere 2.3% last year, close to its lowest level in 30 years, before rising slightly to 2.5% this July. This is a long way below the double-digit rates which many countries experienced in the 1970s and early 1980s.It is also less than most forecasters had predicted. The panel of economists which The Economist polls each month said that America’s inflation rate would average 3.5% in 1995. In fact, it fell to 2.6% in August, and is expected to average only about 3% for the year as a whole. In Britain and Japan inflation is running half a percentage point below the rate predicted at the end of last year. This is no flash in the pan; over the past couple of years, inflation has been consistently lower than expected in Britain and America.Economists have been particularly surprised by favorable inflation figures in Britain and the Unite States, since conventional measures suggest that both economies, and especially America’s, have little productive slack. America’s capacity utilization, for example, hit historically high levels earlier this year, and its jobless rate (5.6% in August) has fallen below most estimates of the natural rate of unemployment — rate below which inflation has taken off in the past.Why has inflation proved so mild The most thrilling explanation is, unfortunately, a little defective. Some economists argue that powerful structural changes in the world have up- ended the old economic models that were based upon the historical link between growth and inflation. The sentence " This is no flash in the pan" (Para. 3) means that（）
Much of the language used to describe monetary policy, such as "steering the economy to a soft landing" or "a touch on the brakes", makes it sound like a precise science. Nothing could be further from the truth. The link between interest rates and inflation is uncertain. And there are long, variable lags before policy changes have any effect on the economy. Hence the analogy that likens the conduct of monetary policy to driving a car with a blackened windscreen, a cracked rear-view mirror and a faulty steering wheel.Given all these disadvantages, central bankers seem to have had much to boast about of late. Average inflation in the big seven industrial economies fell to a mere 2.3% last year, close to its lowest level in 30 years, before rising slightly to 2.5% this July. This is a long way below the double-digit rates which many countries experienced in the 1970s and early 1980s.It is also less than most forecasters had predicted. The panel of economists which The Economist polls each month said that America’s inflation rate would average 3.5% in 1995. In fact, it fell to 2.6% in August, and is expected to average only about 3% for the year as a whole. In Britain and Japan inflation is running half a percentage point below the rate predicted at the end of last year. This is no flash in the pan; over the past couple of years, inflation has been consistently lower than expected in Britain and America.Economists have been particularly surprised by favorable inflation figures in Britain and the Unite States, since conventional measures suggest that both economies, and especially America’s, have little productive slack. America’s capacity utilization, for example, hit historically high levels earlier this year, and its jobless rate (5.6% in August) has fallen below most estimates of the natural rate of unemployment — rate below which inflation has taken off in the past.Why has inflation proved so mild The most thrilling explanation is, unfortunately, a little defective. Some economists argue that powerful structural changes in the world have up- ended the old economic models that were based upon the historical link between growth and inflation. The passage shows that the author is （） the present situation.
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