Gwd20-q27

A significant number of complex repair jobs carried out by Ace Repairs have to be reworked under the company’s warranty.  The reworked jobs are invariably satisfactory.  When initial repairs are inadequate, therefore, it is not because the mechanics lack competence; rather, there is clearly a level of focused concentration that complex repairs require that is elicited more reliably by rework jobs than by first-time jobs.

The argument above assumes which of the following?

1. There is no systematic difference in membership between the group of mechanics who do first-time jobs and the group of those who do rework jobs.
2. There is no company that successfully competes with Ace Repairs for complex repair jobs.
3. Ace Repairs’ warranty is good on first-time jobs but does not cover rework jobs.
4. Ace Repairs does not in any way penalize mechanics who have worked on complex repair jobs that later had to be reworked.
5. There is no category of repair jobs in which Ace Repairs invariably carries out first-time jobs satisfactorily.

   Answer: a

没有思路，请大家指点，万分感谢啊！

A significant number of complex repair jobs carried out by Ace Repairs have to be reworked under the company’s warranty.  The reworked jobs are invariably satisfactory.  When initial repairs are inadequate, therefore, it is not because the mechanics lack competence; rather, there is clearly a level of focused concentration that complex repairs require that is elicited more reliably by rework jobs than by first-time jobs.

这题我也做错了。我查了一下，invariably是”永不变的，始终不变的“的意思。也就是说reworked job一直是很满意的。这说明do first-time job的member和do rework job的member都技术水平都差不多。

这题属于排除他因的ASSUMPTION.
就是说两个REPAIR JOBS之所以区别很大, 不是由于人员不同而造成的.

这种题一般是给出一个现象, 然后作者给出自己的原因来解释这个现象. 那作者的假设就没有其他的原因从而导致这个现象的发生.
比如说:
THERE IS A DEAD CAT ON THE ROAD, SO IT MUST BE RUN OVER BY A CAR.
现象是有路上有只死猫, 我的解释是它被车给压死了. 那么我的假设就是, 这猫不是被其他东西杀害的, 比如这猫不是被狗给咬死的.(这例子有点残忍, 希望喜欢小动物的XDJM们不要介意).

E 无关

修理工种不是文章讨论的范围

文章的解释中，并未提及工种的区分。即使对E取菲，也不影响结论的成立与否。两种分类并不互相影响