[求助] prep-1-58

qxlsh

58.
   (34705-!-item-!-188;#058&007581)

Roland:  The alarming fact is that 90 percent of the people in this country now report that they know someone who is unemployed.

Sharon:  But a normal, moderate level of unemployment is 5 percent, with 1 out of 20 workers unemployed.  So at any given time if a person knows approximately 50 workers, 1 or more will very likely be unemployed.

Sharon's argument relies on the assumption that

(A) normal levels of unemployment are rarely exceeded

(B) unemployment is not normally concentrated in geographically isolated segments of the population

(C) the number of people who each know someone who is unemployed is always higher than 90% of the population

(D) Roland is not consciously distorting the statistics he presents

(E) knowledge that a personal acquaintance is unemployed generates more fear of losing one's job than does knowledge of unemployment statistics

在A和B之间徘徊了很久（答案是B），请哪位帮忙解释一下A和B。谢谢！

在A和B之间徘徊了很久（答案是B），请哪位帮忙解释一下A和B。谢谢！

[此贴子已经被作者于2007-12-30 22:30:17编辑过]

GMMBA

这里是SC区！ 

取非削弱，必须是削弱结论。A削弱的是前提（a normal, moderate level of unemployment is 5 percent）

qxlsh

不好意思,麻烦版主帮忙转移到"逻辑区" 去一下，谢谢！

qxlsh

A和B都不太明白。

请问：如果对Ｂ取反，即人口如果normally concentrated in geographically isolated segments of the population，又会怎么样呢?

谢谢解答！

[此贴子已经被作者于2008-1-1 10:22:39编辑过]