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GMAT2019OG阅读文章--现象解释类
生词多，文章框架不知道该怎么分析，能否请各位大神分析解答一下这篇文章的4道题目？（标红是答案） 做题时真的很懵，遇到这类生词多的文章有什么办法吗？ 恳请大神解答，恳请大神支招~ 感谢！
When asteroids collide, some collisions cause an asteroid to spin faster; others slow it down. Ifasteroids are all monoliths-single rocks-undergoingrandom collisions, a graph of their rotation ratesshould show a bell-shaped distribution with statistical "tails" of very fast and very slow rotators. If asteroidsare rubble piles, however, the tail representing thevery fast rotators would be missing, because anyloose aggregate spinning faster than once every fewhours (depending on the asteroid's bulk density)
would fly apart. Researchers have discovered that all but five observed asteroids obey a strict limit onrate of rotation . The exceptions are all smaller than200 meters in diameter, with an abrupt cutoff for asteroids larger than that.
The evident conclusion-that asteroids larger than200 meters across are multicomponent structures orrubble piles-agrees with recent computer modeling of collisions, which also finds a transition at that diameter. A collision can blast a large asteroid to bits, but after the collision those bits will usually moveslower than their mutual escape velocity. Over severalhours, gravity will reassemble all but the fastest pieces into a rubble pile. Because collisions amongasteroids are relatively frequent, most large bodieshave already suffered this fate. Conversely, mostsmall asteroids should be monolithic, because impact fragments easily escape their feeble gravity.
The passage implies which of the following about the five asteroids mentioned in line 12 ? (A) Their rotation rates are approximately the same. (B) They have undergone approximately the samenumber of collisions. (C) They are monoliths. (D) They are composed of fragments that haveescaped the gravity of larger asteroids. (E) They were detected only recently.
The discovery of which of the following would call into question the conclusion mentioned in line 16 “that asteroids larger than200 meters across are multicomponent structures orrubble piles”? (A) An asteroid 100 meters in diameter rotating at a rate of once per week (8) An asteroid 150 meters in diameter rotating at a rate of 20 times per hour (C) An asteroid 250 meters in diameter rotating at arate of once per week
(D) An asteroid 500 meters in diameter rotating at arate of once per hour
(E) An asteroid 1,000 meters in diameter rotating at a rate of once every 24 hours
According to the passage, which of the following is a prediction that is based on the strength of the gravitational attraction of small asteroids?
(A) Small asteroids will be few in number.
(B) Small asteroids will be monoliths.
(C) Small asteroids will collide with other asteroids very rarely.
(D) Most small asteroids will have very fast rotation rates .
(E) Almost no small asteroids will have very slow rotation rates.
The author of the passage mentions "escape velocity" (see line 22) in order to help explain which of the following?
(A) The tendency for asteroids to become smaller rather than larger over time
(B) The speed with which impact fragments reassemble when they do not escape anasteroid's gravitational attraction after a collision
(C) The frequency with which collisions amongasteroids occur
(D) The rotation rates of asteroids smaller than200 meters in diameter
(E) The tendency for large asteroids to persist after collisions
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发表于 2019-3-11 18:26:04
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