Board logo

标题: 问两道prep上的题,求解释! [打印本页]

作者: Ferris1992    时间: 2013-1-21 07:23     标题: 问两道prep上的题,求解释!

21.    Traces of cultivated emmer wheat have been found among the earliest agricultural remains of many archaeological sites in Europe and Asia.  The only place where the wild form of emmer wheat has been found growing is a relatively narrow strip of southwest Asia.  Since the oldest remains of cultivated emmer wheat yet found are from village sites in the same narrow strip, it is clear that emmer wheat was first domesticated somewhere in that strip.

Which of the following, if true, most strengthens the argument?

(A) The present-day distribution of another wild wheat, einkorn, which was also domesticated early in the development of agriculture, covers a much larger area of southwest Asia.
(B) Modern experiments show that wild emmer wheat can easily be domesticated so as to yield nearly as well as traditionally domestic strains.
(C) At the time when emmer wheat was first cultivated, it was the most nutritious of all the varieties of grain that were then cultivated.
(D) In the region containing the strip where wild emmer wheat has been found, climatic conditions have changed very little since before the development of agriculture.
(E) It is very difficult, without genetic testing, to differentiate the wild form of emmer wheat from a closely related wild wheat that also grows in southwest Asia.
这道直接不懂,跟天气有啥关系呀...

22.   In the late 1980s, the population of sea otters in the North Pacific began to decline.  There are two plausible explanations for the decline:  predation, possibly by killer whales, or disease.  Of these two, disease is the more likely, since a concurrent sharp decline in populations of seals and sea lions is believed to have been caused by disease, and diseases that infect these creatures are likely to be able to infect sea otters also.

Which of the following, if true, most seriously weakens the reasoning?

(A) Killer whales in the North Pacific usually prey on seals and sea lions but will, when this food source is scarce, seek out other prey.
(B) There is no indication that the sea otter population at any North Pacific location declined in the 1980s because of substantial numbers of sea otters migrating to other locations.
(C) Along the Pacific coast of North America in the 1980s, sea otters were absent from many locations where they had been relatively common in former times.
(D) Following the decline in the population of the sea otters, there was an increase in the population of sea urchins, which are sea otters' main food source.
(E) The North Pacific populations of seals and sea lions cover a wider geographic area than does the population of sea otters.
我懂A的意思,但为什么不选C呢?
麻烦大家帮忙啊...我的逻辑实在太弱了,而且总是排除剩两个答案,然后选了个次的....
作者: winnielxx    时间: 2013-1-21 19:47

1. 应该用排除法,因为文章结论是关于wild emmer和种植的emmer的推论,所以没有同时出现这两个东西的选项都应该排除。
2. c选项说的意思就是sea otter减少,没有提到减少的原因,文章讨论的是到底什么使他们减少了。
作者: liuqiangde    时间: 2013-1-22 06:50

第一道题可以简化理解为有一个驯养后的物种一般是被认为存在与欧洲与亚洲,但曾经发现这个物种在被驯养前在亚洲一个很小的地区留下了痕迹。因此认定最早驯养这个物种的地区应该就是在亚洲那个小块地区里。此题为增强支持题。
A,无关选项,本体是就该题干中物种进行讨论,但选项中提出了另一个物种,并且提到这个物种的早期被驯养的范围更大,一点关系都没有。
B,无关选项,只是简洁说明该物种容易被驯养,与该物种和亚洲那块地区连不上关系。
C,无关选项,只是简洁说明该物种(其实是种谷物啦)的营养在驯养初期比较不错。和其在哪处被驯养有何联系?
D,比较隐晦的选项,让我想起了狒狒逻辑的一道题,待会说。
E,乍一看很有联系,其实没有联系。这两种谷物就算用遗传测试测出相同或不同,或出现在同一个地区又如何呢?还是无法说明题干中的谷物曾经“最早”出现在亚洲。

D是比较带点天马行空的选项,其实是小支持,但是在这几个选项里已经算是最合适的。因为天气稳定,该地区的农业才能发展,这是常识么。GMAT是需要常识的,虽然很多机构不赞成。

此题逻辑链:
背景-该物种的野生版本只存在于亚洲某片区域。
原因-该区域的人工繁殖后的版本也存在于该区域。
结论-其人工繁殖版本最早一定出现于该区域。

D选项很好利用了此题的背景:此物种野生版本只存在于该区域,而该区域仅在天气改善后才开始适合农业发展。换句话说在天气改善之前,该地区的这个物种是无法被人工繁殖的;于是天气改善后,你猜只存于该区域的该物种要是能被人工繁殖,应该会来自于哪里呢?

这题的逻辑有点像在问:你欠了我100元,你只欠我这么一个人,当你有钱想要还钱的时候,你这100元还给谁?同样,这个谷物只存在于亚洲这块,当天气改善,这块开始适合农业,而这谷物又被人成功种植后,它是不是该最早出现在这块地呢?

貌似我说的复杂了点。但如果实战就我这PACE-2分钟1题要我选,我可能未必选D。因为这个逻辑比较绕,绕了好几个圈了。让我想起狒狒逻辑有一题说得是“一个公司决定让其所有职员都上一遍专业课以便学习更多的经验应付工作”,题目要求是削弱,答案是“公司的资深员工已经工作十年以上”(因此已经没有学习更多经验的上升空间,工作也已应付得很专业)。都是挺绕脑子的题。

第二题说的是水懒的数量锐减,原因可能是捕食者-杀人鲸或病毒。但病毒的可能性大点,因为和其在同一地区生存的海狮什么因为病毒也数量锐减,这些海狮可能把病毒传染给了水懒。此题问的是削弱。

削弱其实比加强简单,削弱无非是削弱其原因或者削弱其结果。

A,我看了一遍就觉得A可能,先放一放。
B,只是排除了一个原因。与提干无关,提干已经说了有2个原因,排不排除第3个都没有意义。
C,C精确重复了文中的意思,只是少了,没说为什么,换言之,C没有明确排除这2个原因中的任何一个,也可能C认为是病毒呢?那岂不是加强了?
D,提供了一个这个情况产生的结果,因为水懒少了,于是它的猎物数量多了。
E,无关选项,这些物种的生存分布和它们数量减少的原因没有任何联系。

此题其实有个很大的暗示,就是另一个原因-杀人鲸。换言之如果是削弱此题,就等于说水懒的减少是因为杀人鲸而不是因为病毒-此为他因;其二个削弱方式就是直接说病毒可能反而促使了水懒的数量增长-因此与数量减少无关,为削弱。很明显,此题为他因法。但我个人认为这个A选项并不完美,虽然它很明确表示因为提干背景提供的资料-海狮数量的减少,使得杀人鲸不得不捕食其他物种,从而促使其他物种的数量也跟着减少。但它并没有明确表示这个其他物种里就有水懒。杀人鲸捕食的范围包括海豚,企鹅,并不局限水懒。一般情况除非出现其他强力的选项,不然只能出下策选择这类暧昧点的。
作者: Ferris1992    时间: 2013-1-23 06:57

在做的时候有点不解,看到这个解答感觉明白了~谢谢!




欢迎光临 国际顶尖MBA申请交流平台--TOPWAY MBA (http://forum.topway.org/) Powered by Discuz! 7.2