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【单选题】
Then something happened to Cosmos. It may have sprung a small leak ; perhaps it struck a tiny asteroid (小行星) or a piece of debris. Nobody knows for sure, but for one reason or another. Cosmos drifted off course. T. S. Kelso, an aeronautics expert at ytical Graphics. which provides satellite-tracking services to NASA, noticed that the orbits of Cosmos and Iridium were bringing the two satellites closer to each other all the time. In February he issued a waming that they would pass within a kilometer of one another. He was right. On Feb. 10, Motorola lost track of Iridium’s signal. Over the next few days, Kelso and others surmised (推测) that what many had feared for years had finally come to pass: two intact (完好无损的) satellites had collided head on.
What had happened to Cosmos and Iridium in February according to Kelso
A.
They had had mechanical problems.
B.
They had struck a tiny asteroid.
C.
They has struck a piece of debris.
D.
They had collided into each other.
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参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】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...
A.
It is very unlikely, but the danger exists.,
B.
Such a collision might occur once every 25 years.
C.
Collisions of smaller asteroids with Earth occur more often than expected.
D.
It’s still too early to say whether such a collision might occur.
【单选题】2011年7月，天文学家发现了一颗直径300米的小行星，它与地球有着相同的公转轨道，并始终在地球前方“打转”。这一发现再次印证了( ) ①自然界是物质的 ②人的意识是物质世界的产物 ③人类社会是物质的 ④世界真正的统一性在于它的物质性
A.
①②
B.
③④
C.
②③
D.
①④