GWD17-Q35 to Q37

GWD17-Q35 to Q37:

(This passage was excerpted from material published in 1996.)

      When a large body strikes a planet or moon, material is ejected, thereby creating a hole in the planet and a local deficit of mass.  This deficit shows up as a gravity anomaly:  the removal of the material that has been ejected to make the hole results in an area of slightly lower gravity than surrounding areas.  One would therefore expect that all of the large multi-ring impact basins on the surface of Earth’s Moon would show such negative gravity anomalies, since they are, essentially, large holes in the lunar surface.  Yet data collected in 1994 by the Clementine spacecraft show that many of these lunar basins have no anomalously low gravity and some even have anomalously high gravity. 
                Scientists speculate that early in lunar history, when large impactors struck the Moon’s surface, causing millions of cubic kilometers of crustal debris to be ejected, denser material from the Moon’s mantle rose up beneath the impactors almost immediately, compensating for the ejected material and thus leaving no low gravity anomaly in the resulting basin.  Later, however, as the Moon grew cooler and less elastic, rebound from large impactors would have been only partial and incomplete.  Thus today such gravitational compensation probably would not occur:  the outer layer of the Moon is too cold and stiff.

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35. Q35:

According to the passage, the gravitational compensation referred to in line 33 is caused by which of the following?

A.     A deficit of mass resulting from the creation of a hole in the lunar surface

B.       The presence of material from the impactor in the debris created by its impact

C.      The gradual cooling and stiffening of the Moon’s outer layer

D.      The ejection of massive amounts of debris from the Moon’s crust

E.       The rapid upwelling of material from the lunar mantle

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36. Q36:

The passage suggests that if the scientists mentioned in line 19 are correct in their speculations, the large multi-ring impact basins on the Moon with the most significant negative gravity anomalies probably

A.      were not formed early in the Moon’s history

B.      were not formed by the massive ejection of crustal debris

C.      are closely surrounded by other impact basins with anomalously low gravity

D.      were created by the impact of multiple large impactors

E.       were formed when the Moon was relatively elastic

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37. Q37:

Which of the following best describes the organization of the passage?

A.      An anomalous finding is cited, the data used to support that finding are analyzed, and the finding is modified.

B.       A theory about a phenomenon is introduced, data seeming to disprove that theory are analyzed, and the theory is rejected.

C.      A phenomenon is described, a finding relating to the phenomenon is discussed, and a possible explanation for that finding is offered.

D.      A debate among scientists regarding the explanation for a particular phenomenon is outlined, and one position in that debate is shown to be more persuasive.

E.       The observation of an astronomical event is described, and two schools of thought about the explanation for that event are discussed.

请问36 为什么选A?

36   Scientists speculate that early in lunar history,

提到早起月亮表面可以compansate 是不低，而且具有延展性，但是后来 Thus today such gravitational compensation probably would not occur:  the outer layer of the Moon is too cold and stiff.

36题目中问你，如果科学加解释正确，那么negative这些hole存在的原因是什么？

推理可得，早期温度不低有延展，所以 compansate,早期之后的温度低，而且stiff，所以不能compansate，所以选a

我想问35题~

我也想问35题。。。。。。

According to the passage, the gravitational compensation referred to in line 33 is caused by which of the following?

A.      A deficit of mass resulting from the creation of a hole in the lunar surface

我觉得应该选A呀。。。。

我有点明白了，

A选项其实是重力不规则（anomaly）的原因，

E选项可以在原文第二段denser material from the Moon’s mantle rose up beneath the impactors almost immediately, compensating for the ejected material

这里找到

同意四楼，

according to passage indicates the info can be found in passage.

我也想问

这篇文章完全读不懂，有没有NN可以讲一下这篇文章的意思和如何定位呀

不是nn，说说我的理解吧

当有物体和月球相撞时，会有物质被放出来，从而在月球表面形成低地或洞，导致低地比低地周围的重力异常低。

提出一个假设，所有的月球表面形成的低地都会表现出反重力（就是低的意思吧我想，不知怎么解释），但是最近的资料显示很多月球表面低地的重力没有低反而很高。

然后科学家们开始提出猜测，在很久很久以前，当有物体撞击月球的时候，导致物质被释放，与此同时，密度很高的mantle会从冲撞物下面马上涌上来弥补被释放的物质，所以就没有导致很低的重力。又由于后来，月亮越来越cooler and less elastic，当撞击物撞击时很少能反弹（即mantle不会涌上来）。所以今天gravitational compensation 不会发生。