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关系数据库规范化理论的研究中，在函数依赖的范畴内， 【20】 达到了最高的规范化程度。
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Bangkok has all the problems of any modern city including world-class traffic jams. It also has some traffic problems unique to Thailand, CNN’s Bangkok Bureau chief, Daninque explains. This used to be the only way some people traveled in Bangkok, by elephant. A long time ago cars replaced them, but some can still be seen in the city, nice for tourists but real problem for city officials. Elephants can cause traffic jam that is already bad to bec6me worse. The city of Bangkok has now ordered the elephants off the streets. Elephant handlers will be fined if police catch them on the streets but most are encouraged to be here in- stead. The city has created an elephant sanctuary so the animals have a place to go instead of roaming the streets. In recent weeks it has turned into somewhat of a local tourist attraction. School children have flocked to the vacant lot for what might be the first time to see a live elephant. So far the elephant rescue program has been a success. Fifteen have been taken off the streets and brought here to the elephant center Twelve of them returned back home to the provinces sort of half way house for Pakiderms. The elephant camp is only a temporary solution to the problem. Thailand does have an elephant round-up once each year in the northern provinces. It is promoted by tourism officials. But city officials are working on a plan to turn their problem into profit. Some are talking about making the elephant camp permanent at a larger location. It could provide tourists the same chance as these school children, to not only see an elephant but to touch one. City officials of Bangkok are working on a plan to turn their pr0blem into ().
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The fossil remains of the first flying vertebrates, the pterosaurs. have intrigued paleontologists for more than two centuries, How such large creatures, which weighed in some eases as much as a piloted hang-glider and had wingspans from 8 to 12 meters, solved the problems of powered flight, and exactly what these creatures were — reptiles or birds — are among the questions scientists have puzzled over.Perhaps the least controversial assertion about the pterosaurs is that they were reptiles. Their skulls, pelvises, and hind feet are reptilian. The anatomy of their wings suggests that they did not evolve into the class of birds. In pterosaurs a greatly elongated fourth finger of each forelimb supported a wing like membrane. The other fingers were short and reptilian, with sharp claws. In birds the second finger is the principal strut of the wing, which consists primarily of feathers. If the pterosaurs walked on ail fours, the three short fingers may have been employed for grasping. When a pterosaur walked or remained stationary, the fourth finger. and with it the wing, could only turn upward in an extended inverted V-shape along each side of the animal’s body.The pterosaurs resembled both birds and hats in their overall structure and proportions. This is not surprising because the design of any flying vertebrate is subject to aerodynamic constraints. Both the pterosaurs and the birds have hollow bones, a feature that represents a savings in weight. In the birds, however, these bones are reinforced more massively by internal struts.Although scales typically cover reptiles, the pterosaurs probably had hairy coats. T.H. Huxley reasoned that flying vertebrates must have been warm-blooded because flying implies a high rate of metabolism, which in turn implies a high internal temperature. Huxley speculated that a coat of hair would insulate against loss of body heat and might streamline the body to reduce drag in flight. The recent discovery of a pterosaur specimen covered in long, dense, and relatively thick hair—like fossil material was the first clear evidence that his reasoning was correct.Efforts to explain how the pterosaurs became airborne have led to suggestions that they launched them- selves by jumping from cliffs, by dropping from trees or even by rising into light winds from the surfaces of waves Each hypothesis has its difficulties. The first wrongly assumes that the pterosaurs’ hind feet resembled a hat’s and could serve as hooks by which the animal could hang in preparation for flight. The second hypothesis seems unlikely because large pterosaurs could not have landed in trees without damaging their wings. The third calls for high waves to channel updrafts. The wind that made such waves however, might have been too strong for the pterosaurs to control their flight once airborne. It can be inferred from the passage that scientists now generally agree that the ().
某开发商在同一时期准备一个住宅小区和一个高档次写字楼，因此他需要建立一个合理的营销推广组织；要求能集中精力管理不同的产品，不用考虑成本费用问题，并确定一套合理的广告方式，他应该做好哪些工作 在公司进行产品定位时，考虑写字楼是针对对外贸易的，希望在选择广告时，选择读者集中、针对性强的不考虑成本的，因此比较合适的是( )。
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