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Are we at the beginning of another Age of Exploration Perhaps even more important, are we at the beginning of 1 Age of Colonization As the population of the world increases towards the point 2 the earth can no longer support all the people 3 on it, the second question becomes urgent. Will we discover a new world, 4 Columbus did, on which human life will be possible At this point in the space age, no one can really answer these questions. We can say, 5 that we will not see tomorrow the kind of space travel that 6 fiction and the movies have shown. It will be a long time before we have flight that run 7 to human colonies on the moon or on, one of the planets. We are not even going to be able to 8 immediate advantages of the minerals that we may find on the planets 9 our own solar system.Great problems must be solved 10 we could send colonists out into place. The distances that must be 11 and the length of time it takes to do that can hardly be 12 . There are also dangers that we still do not realty understand, from radiation, for example, or from pieces of matter 13 in space, or from contamination forms of life that might 14 there. There is also need for humans to take their own environment into space 15 them. So far no "island" has been discovered in space on which people can exist without systems that 16 life, and these systems must accompany any future space 17 Finally, on the most practical 18 there has to be enormous expense 19 in space exploration. The U.S. and Russian governments have already spent billions of dollars for projects 20 which they can receive a return only in knowledge and not in money.
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Satellite communication are so up-to-date that even when ______ in the middle of the Pacific, businessmen can contact their offices as if they were next door.
To fight against computer crimes, a computer system needs a sure way of identifying its right users and rejecting those who are not entitled to use it. The identification system should be quick, simple, and convenient.At present, signatures are widely used to identify credit card holders, but it takes an expert to detect a good forgery. Sometimes even a human expert is fooled, and there is no reason to believe that a computer could do any better.Photographs are also sometimes used for identification. But, people find it inconvenient to stop by a credit card company aid to be photographed. Companies might lose business if they made the pictures under absolute requirement. Also, photographs are less useful these days, when people frequently change their appearance by changing the way they wear their hair. Finally, computer programs for analyzing photographs are still highly experimental.Cash-drawing systems often use two identification numbers: One is recorded on a magnetic stripe on the identification cards, and the other is given to the CRS holder. When the user inserts his card into the cash-drawing terminal, he keys in the identification number he has been given. The computer checks to see that the number recorded on the card and the other keyed in by the user refer to the, same person.For a long time, fingerprints have provided a method of positive identification. But they suffer from two problems. One is that there is no simple system for comparing fingerprints electronically, the other is that because most people associate being fingerprinted with being arrested; they almost surely would resist being fingerprinted for routine identification.Voiceprints have been suggested. With these, the user has only to speak a few words for the computer to analyze his voice. There are no psychological problems here. And technically it"s easier to take and analyze voiceprints than fingerprints. However, it has yet to be proved that the computer cannot be fooled by imitation. Also, the voice is subjected to the noise and distortion of a telephone line.Even lipprints have been suggested. But it"s doubtful that kissing computers will ever catch on. The passage is organized by ______.
No woman can be too rich or too thin. This saying often attributed to the late Duchess of Windsor embodies much of the odd spirit of our times. Being thin is deemed as such virtue. The problem with such a view is that some people actually attempt to live by it. I myself have fantasies of slipping into narrow designer clothes. Consequently, I have been on a diet for the better—or worse—part of my life. Being rich wouldn"t be bad either, but that won"t happen unless an unknown relative dies suddenly in some distant land leaving me millions of dollars.Where did we go off the track When did eating butter become a sin, and a little bit of extra flesh unappealing. If not repellent All religions have certain days when people refrain from eating, and excessive eating is one of Christianity"s seven deadly sins. However until quite recently, most people had a problem getting enough to eat. In some religious groups, wealth was a symbol of probable salvation and high morals, and fatness a sign of wealth and well-being.Today the opposite is true. We have shifted to thinness as our new mark of virtue. The result is that being fat—or even only somewhat overweight—is bad because it implies a tack of moral strength.Our obsession with thinness is also fueled by health concerns. It is true that in this country we have more overweight people than ever before, and that, in many cases, being overweight correlates with an increased risk of heart and blood vessel diseases. These diseases, however, may have as much to do with our way of life and our high-fat diets as with excess weight. And the associated risk of cancer in the digestive system may be more of a dietary problem—too much fat and a lack of fiber—than a weight problem.The real concern, then, is not that we weigh too much, but that we neither exercise enough nor eat well. Exercise is necessary for strong bones and both heart and lung health. A balanced diet without a lot of fat can also help the body avoid many diseases. We should surely stop paying so much attention to weight. Simply being thin is not enough. It is actually hazardous if those who get (or already are) thin think they are automatically healthy and thus free from paying attention to their overall lifestyle. Thinness can be pure vainglory. The author criticizes women"s obsession with thinness ______.
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