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判断题All microcomputer CD-ROM drivers can play audio compact disks.
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判断题The author suggests that we should use English in making programs.
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判断题The success of any distance education effort relies on the facilitators only.
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判断题The only purpose of parallel systems is to achieve maximum speedup on a single problem.
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判断题
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判断题All inspection bodies are governmental. ( )
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判断题An assembler is a person who makes an assembly program.
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判断题In practice
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判断题GBP 97 per metric ton CIF Copenhagen.
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判断题Multimedia can save a teachers time.
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判断题Web sites cannot share the same IP address.
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判断题F. P. A
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判断题The key factor that helps make distributed systems popular is economics.
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判断题Promissory notes can only be commercial notes
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判断题The contract can be concluded by other forms besides the written form or oral form.
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判断题According to the British Law
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判断题6.Computers seem to be put to little use in private homes.
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判断题Ⅰ.Too Many People Figures and numerous facts prove that there are already, and certainly that where will be, too many people. Simply calculating the lengths of time necessary to double the world's population is instructive. Impressively, the time required grows ever shorter: 6,000 years before Christ, 1,000,000 years were necessary to double the population, then about 1,650 years after Christ only 1,000 around the 1850's 200 years, in 1930's 80 years. Currently, the world's population doubles every 37 years. What would happen if the population were to continue doubling in volume every 37 years? According to recent calculations, maintaining such a rhythm of growth would result in 60 million billion people on the earth in 900 years, which represents 120 inhabitants per square meter. Optimists believe and often assert that science will indeed find solutions to the problem of overcrowding, namely by providing the means to immigrate to other planets. But this solution is totally impossible. In effect, even if it should become possible, 50 years would be sufficient for the 60 million billion persons to multiply to the point of populating Venus, Mercury, Mars, the Moon and the satellites of Jupiter and Saturn with a density equal to that of the Earth. Ⅱ.Food shortage Today, a good part of humanity suffers from malnutrition or from undernourishment. Some think that the recent scientific discoveries applied to agriculture and known under the name of "green revolution" will resolve the problem. Nothing is less certain. Promoters of the revolution themselves believe that it can offer only a respite of ten or twenty years. In underdeveloped countries, although mostly agricultural, the lag in food production in relation to population growth increases more and more. As the crisis worsens these countries will have to import food. But from where? Ⅲ.A Dying Planet The world's population explosion is the source of a whole series of environmental deteriorations, which in time can have disastrous consequences. Because the population—food imbalance makes it necessary to increase agricultural production "at any price", methods often harmful to the environment are used without judgment. For example, the construction of huge dams to irrigate hundreds of thousands of acres can in fact provoke catastrophes. Thus, the Aswan Dam currently prevents the deposit of fertile silts brought each year by the flooding of the Nile. The result will obviously be a decrease in the fertility of the Delta lands. Damming the Mekong risks the same consequences for Vietnam and neighbouring countries. Fertilizers, synthetic pesticides, DDT can be devastating, transforming complex ecosystems, necessary for the conservation of the environment, into simple ecosystems. Certain situations are perceived as dangerous only when they become critical enough to cause numerous deaths. Smog is an example. In London in 1952 it caused some 4,000 deaths. This incident provoked an awakening of conscience and resulted in decisions, which have proven effective. But smog presents still other dangers: namely, it destroys plants which offer little resistance, and whose oxygen production is indispensable to us, and it changes the earth's thermal equilibrium. For these forms of pollution as for all the others, the destructive chain of cause and effect goes back to a prime cause: "too many cars, too many factories, too many detergents, too many pesticides, more and more trails left by supersonic jets, inadequate methods for disinfecting sewers, too little water, too much carbon monoxide. The cause is always the same: too many people on the earth./
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判断题Method of calculating weight by conditioned weight is suitable to those cargoes whose moisture contents are not stable , such as wool, silk , etc.
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判断题The bid bond will be refunded if the bidder fails to get the award.
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