新GRE阅读理解36套每日讨论--60（群178674184）

普渡哥

Question 4 is based on the following reading passage.
According to astronomer S.A. Phinney, kicking a rock
hard enough to free it from Earth's gravity would require
a meteorite capable of making a crater more than 60
miles across. Moreover, even if Earth rocks were freed
by meteorite impact, Mars's orbit is much larger than
Earth's, so Phinney estimates that the probability of
these rocks hitting Mars is about one-tenth as great
as that of Mars's rocks hitting Earth. To demonstrate
this estimate, Phinney used a computer to calculate
where 1,000 hypothetical particles would go if ejected
from Earth in random directions. He found that 17
of the 1,000 particles would hit Mars.


4. Which of the following, if true, would cast most
doubt on Phinney's estimate of the probability of
Earth rocks hitting Mars?
○A Rather than going in random directions, about
25 percent of all particles ejected from Earth
go in the same direction into space.
○B Approximately 100 meteorites large enough to
make a noticeable crater hit the Earth each year.
○C No rocks of Earth origin have been detected
on Mars.
○D The velocity of rocks escaping from Earth's gravity is
lower than the velocity of meteorites hitting the Earth.
○E No craters more than 60 miles across have
been found on Mars.

元宝盒子

c        （字数补丁）

晏小川

这个题应该选A吧

元宝盒子

召唤普哥现身~

普渡哥

正确答案是：

A

大家加油！现在做阅读的越来越少了。。。。

snowmelt

前阵子复习作文，搁置了阅读。结果突然以模拟，傻眼了。悲剧啊

普渡哥

加油加油，每天坚持做CD的题目啊！！

yifenliu1

A