LSAT-3-1-12

mariezhu

  

12.   Leachate is a solution, frequently highly contaminated, that develops when water permeates a landfill site. If and only if the landfill’s capacity to hold liquids is exceeded does the leachate escape into the environment, generally in unpredictable quantities. A method must be found for disposing of leachate. Most landfill leachate is send directly to sewage treatment plants, but not all sewage plants are capable of handling the highly contaminated water.

Which one of the following can be inferred from the passage?

(A) The ability to predict the volume of escaping landfill leachate would help solve the disposal problem.

(B) If any water permeates a landfill, leachate will escape into the environment.

(C) No sewage treatment plants are capable of handling leachate.

(D) Some landfill leachate is send to sewage treatment plants that are incapable of handling it.（E）

(E) If leachate does not escape from a landfill into the environment, then the landfill’s capacity to hold liquids has not been exceeded.

大全给的答案是E，可是我按照题目推理觉得E恰恰是错的，推理如下，请大牛指正：

If and only if the landfill’s capacity to hold liquids is exceeded does the leachate escape into the environment即leachate escape -> capacity exceeded, 从这里只能得出 capacity not exceeded -> leachate not escape, 不能推出leachate not escape -> capacity not exceeded

此外我觉得D倒是个很好的答案：

Most landfill leachate is send directly to sewage treatment plants, but not all sewage plants are capable of handling the highly contaminated water.可以推出Some landfill leachate is send to sewage treatment plants that are incapable of handling it.

weiyu

You might pay attention to "If and only if the landfill’s capacity to hold liquids is exceeded does the leachate escape into the environment, generally in unpredictable quantities"


if and only if A, B will occur:     A<->B so E is right.


D is tricky:Some landfill leachate is send to sewage treatment plants that are incapable of handling it；一些L被送到了不能处理他们的污水厂


The argument mentions that: Most landfill leachate is send directly to sewage treatment plants, but not all sewage plants are capable of handling the highly contaminated water


多数的L被直接送到处理厂，但不是所有的处理厂都能处理被污染的水。可能所有被污染的水都被送到能处理污水的处理厂了。

mariezhu

明白了，我只把注意力放在了only if上。


多谢