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Flying the Hypert Skies A little airplane has given new meaning to the term "going hyper. " The Hyper-X recently broke the record for air-breathing jet planes when it traveled at a hypersonic speed of seven times the speed of sound. That’s about 5,000 miles per hour. At this speed, you’d get around the world -- flying along the equator (赤道) -- in less than 5 hours. The Hyper-X is an unmanned,experimental aircraft just 12 feet long. It achieves hypersonic (超音速的) speed using a special sort of engine known as a scramjet. It may sound like something from a comic book,but engineers have been experimenting with scramjets since the 1960s. For an engine to burn fuel and produce energy, it needs oxygen. A jet engine, like those on passenger airplanes, gets oxygen from the air. A rocket engine typically goes faster but has to carry its own supply of oxygen. A scramjet (紧急刹车) engine goes as fast as a rocket, but it doesn’t have to carry its own oxygen supply. A scramjet’s special design allows it to obtain oxygen from the air that flows through the engine. And it does so without letting the fast-moving air put out the combustion (燃烧) flames. However, a scramjet engine works properly only at speeds greater than five times the speed of sound. A booster rocket carried the Hyper-X to an altitude of about 100,000 feet for its test flight. The aircraft’s record-beating flight lasted just 11 seconds. Although the little plane’s self-powered flight lasted only 11 seconds, that brief journey on March 27 makes a major milestone on the way to a new breed of very fast airplanes, comments Werner J. A. Dahm of the University of Michigan in Ann Arbor. In the future, engineers predict, airplanes equipped with scramjet engines could transport cargo quickly and cheaply to the brink of space. Such hypersonic jets could potentially carry passengers anywhere in the world in just a few hours. Out of the three experimental Hyper-X aircrafts built for NASA, only one is now left. The agency has plans for another 11-second hypersonic flight, this time at 10 times the speed of the sound. What did Werner J. A. Dahm of the University of Michigan say about the Hyper-X test flight
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药物信息包括药事法规和药品价格，这说明药物信息( )
From the very beginning, water has furnished man with a source of food and a highway to travel. The first civilizations arose (76) water was the dominant element in the environment, a challenge (77) man’s ingenuity. The Egyptians invented the 365-day calendar (78) the Nile’s annual flooding. The Babylonians (79) were among the most famous law-makers in ancient times, invented laws (80) water usage. Water inspired the Chinese to build a 1,000 miles’ canal, a complex system (81) , after 2,500 years, remains particularly in use and still commands the astonishment of engineers. But the ancients never found complete solutions (82) their water problem. The Yellow River is also known as "China’s Sorrow". It is so unpredictable and dangerous (83) in a single flood it has caused a million deaths. Floods slowed the great (84) of the Indus River Valleys, and innumerable damages ruined much of its land. Today, water dominates man as it always has done. Its presence continues to influence the location of his homes and cities; its violent variability can (85) man or his herds or his crops; its routes link him to his fellows; its immense value may add to the already dangerous political conflicts. There are many examples of this in our own time.
________类是提供线程操作和管理的类。
《刑法》第305条规定：在刑事诉讼中，证人、鉴定人、记录人、翻译人对与案件有重要关系的情节，故意作虚假证明、鉴定、记录、翻译，意图陷害他人或者隐匿罪证的，处三年以下有期徒刑或者拘役；情节严重的，处三年以上七年以下有期徒刑。 在一合同纠纷案件中，原告甲为了争取胜诉，花了500元请乙对本案的关键情节作虚假陈述，乙明知这是虚假的陈述仍然出庭为甲作证，致使一审法院据此判令原告甲胜诉，并造成被告经济损失5万元。后被告不服上诉至二审法院，二审法院查明了其中的原委，撤销了原审判决，发回一审法院重审。本案中乙的行为是否构成本条规定的罪请说明理由。
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