Prep1 16

[CherrieLi]

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

答案是A, 我選C,
因為覺得A中, 即使uranium in deposits on land快depleted, 從seawater中取得uranium的cost還是比較高阿!?

請各位大大幫忙

[Huang Hsin-Yi]

（a)選項的意思是
　
　　如果地上的釉快用完了　　即使是在海上開發成本高　還是具有商業價值
反之如果地上還一大堆釉　　　在海上開發成本高的條件下是絕對沒價值的

（C)選項評量開發技術成本的高低　若沒考慮釉在地上存量的問題　是無效的
（就像我在地上有很多釉又容易開採　就算是海上開發成本低　對我也構不成誘因）