prep1-16,没有讨论过,百思不得解.

16.            (27621-!-item-!-188;#058&003223)

Most of the world's supply of uranium currently comes from mines.  It is possible to extract uranium from seawater, but the cost of doing so is greater than the price that uranium fetches on the world market.  Therefore, until the cost of extracting uranium from seawater can somehow be reduced, this method of obtaining uranium is unlikely to be commercially viable.

Which of the following would it be most useful to determine in evaluating the argument?

(A) Whether the uranium in deposits on land is rapidly being depleted

(B) Whether most uranium is used near where it is mined

(C) Whether there are any technological advances that show promise of reducing the cost of extracting uranium from seawater

(D) Whether the total amount of uranium in seawater is significantly greater than the total amount of uranium on land

(E) Whether uranium can be extracted from freshwater at a cost similar to the cost of extracting it from seawater

选A, 我选C.

把A取正向解释, 并不能支持原文;反向解释也不能反驳原文的结论呀!

请教大家!!!

17.            (27669-!-item-!-188;#058&003302)

Urban air contains more sulfur dioxide than does rural air, and plants in cities typically grow more slowly than do plants in rural areas.  In an experiment to see how much of the difference in growth is due to sulfur dioxide, classes in an urban and a rural school grew plants in greenhouses at their schools and filtered the greenhouse air to eliminate sulfur dioxide.  Plants in the urban greenhouse grew more slowly than those in the rural greenhouse.

Which of the following, if true, would it be most important to take into account in evaluating the result?

(A) The urban school was located in a part of the city in which levels of sulfur dioxide in the air were usually far lower than is typical for urban areas.

(B) At both schools, the plants in the greenhouses grew much more quickly than did plants planted outdoors in plots near the greenhouses.

(C) The urban class conducting the experiment was larger than the rural class conducting the experiment.

(D) Heavy vehicular traffic such as is found in cities constantly deposits grime on greenhouse windows, reducing the amount of light that reaches the plants inside.

(E) Because of the higher levels of sulfur dioxide in the air at the urban school, the air filters for the urban school's greenhouse were changed more frequently than were those at the rural school.

选D, 它 没有说明为什么城里的GREEN HOUSE中的植物长得慢的事情呀?

感谢大家的回复

16 我以为：这段话的结论本身在说直到海水提取价格便宜，海水提取才可能商业化，问题要求对此话进行评估，这个结论是否有道理？

C评估该结论是重新回到结论，说有没有新技术使之降价，而对本结论没有作出是否有道理的评估

A评估则是说看看世界陆地铀矿是否已经耗尽，

如果耗尽，无论海水提取贵不贵，都不得不从海水提取，则结论错误；

如果没有耗尽，则结论正确。

第一题，我并没有想的那么复杂，看完文章立刻推出assump贵了人们就不用，所以选A:如果都地上的开发完了，海里再贵也要用

第二题，问evaluate温室实验的正确性.选项D指出在城市里除了Sulfur之外，还有排放气体使植物缺乏光线，所以这个实验就不能正确比较农村和城市了。所以是正确选项。

ps.再次求助，大虾能否把包含发帖子的按扭的界面发到我信箱里，我如何也找不到了，万分感谢！或者给我电话也行！yi_chi_neu(A) hotmail.com

谢谢楼上两位大侠.

那是不是就是说:EVALUATE的题目答案,不是对原文结论否定,就是肯定咯?

17题说是去evaluate the results 说明结果已经出来了 而一般地不是去evaluate the argument

这里的result是在滤去sulfur dioxide的rural 和 urban greenhouse里面   urban 植物还是长的慢

这是个对照实验 说明
        sulfur dioxide已经不是造成这个现象的原因 所以只能是它因

也就是D      different amount of light

我觉得16题的B也有道理啊

如果这种矿产必须就地开采，就地使用，就算是海底的贵，海上要用也必须从海底开采啊？

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