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>> 成人高等教育 / 中国法制史
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佳题速递：
2[名词解释题]
频率
河南理工大学
10、
Unless we spend money to spot and prevent asteroids (小行星)now, one might crash into Earth and destroy life as we know it, say some scientists. Asteroids are bigger versions of the meteoroids (流星)that race across the night sky. Most orbit the sun far from Earth and don‘t threaten us. But there are also thousands of asteroids whose orbits put them on a collision course with Earth. Buy $50 million worth of new telescopes right now. Then spend $10 million a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one, the scientists say, we‘ll have a way to change its course. Some scientists favor pushing asteroids off course with nuclear weapons. But the cost wouldn‘t be cheap. Is it worth it?Two things experts consider when judging any risk re:1)How likely the event is;and 2)How bad the consequences if the event occurs. Experts think an asteroid big enough to destroy lots of life might strike Earth once every 500, 000 years. Sounds pretty rare—but if one did fall, it would be the end of the world. “If we don‘t take care of these big asteroids, they‘ll take care of us, ”says one scientist. “It‘s that simple. ” The cure, though, might be worse than the disease. Do we really want fleets of nuclear weapons sitting around on Earth?“The world has less to fear from doomsday (毁灭性的)rocks than from a great nuclear fleet set against them, ”said a New York Times article.
1. What does the passage say about asteroids and meteoroids?A) They are heavenly bodies different in composition.
B) They are heavenly bodies similar in nature. 【外语教育&网大学英语2 1964年出现第一台计算机问世。信息检索 67、在世界的本原上，意识比物质更加基本。毛泽东思想和中国特色社会主义理论体系概论 链接是将源程序、目标程序和库函数链接到一起，生成可执行程序。C语言程序设计 42[填空题]
半衰期为10天的放射性元素净重16克，50天后其净重为 克。物理化学