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>> 成人高等教育 / 计算机网络
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佳题速递：
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&网综合英语（二） 8、面状材料的制作方法是（ ） （分数：3 分）
A. 加法
B. 减法
C. 既有加法，也有减法
D. 变形不变量法学前儿童美术教育 在垄断市场上，长期均衡的条件是（ ）
a. MR=SMCb. MR=MC，AR=ACc. MR=LMC=SMC d. MR=LMC西方经济学 雌二醇可以和2，4-二硝基苯肼形成有色的腙类衍生物。药物化学 共享环境：指的是在同一个家庭长大的子女所共同（ ）的环境，包括了这个家庭的经济状况、家庭气氛、教养方式、父母的教育程度与社会地位以及周边环境等。社会心理适应 21、以下不属于太阳能光伏电池材料的是（）。
A. 硫化镉
B. 砷化镓
C. 氟化铵
D. 多晶硅太阳能光伏发电系统与应用