Prep T1-16

[hwatai]

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



困擾的選項是C，回到原文，提到是from mines與from seawaters的成本差異；即使如C所說from seawaters成本下降，仍不能說明是否有比from mines還來得便宜，因此不適合用作evaluate之用

答案為A

[dibert8]

是的. (C) 不會改變現況 (i.e. 沒有商業化的急迫性),是不是有這個技術就不是那麼重要了.
(A) (C) 的差異在於 (A) 提供了動機.

[kaijen]

這一題我也選了(C)
我覺的錯的地方在於(C)重複了原題的假設 因此無法評價該論題
until the cost of extracting uranium from seawater can somehow be reduced
(C) Whether there are any technological advances that show promise of reducing the cost of extracting uranium from seawater

[hey]

江璞老師曾說過, 答案的選項最好不要從技術面方面來下手, 而(C)就是犯了此種錯誤

[kigosam]

這一題我也選了(C)
我覺的錯的地方在於(C)重複了原題的假設 因此無法評價該論題
until the cost of extracting uranium from seawater can somehow be reduced
(C) Whether there are any technological advances that show promise of reducing the cost of extracting uranium from seawater

沒錯，（c）是這一題的statement，是他的前提「but the cost of doing so is greater than the price that uranium fetches on the world market.」，前提是沒有辦法變動的（這也是其中一種讓你混淆的選項）

另外，（c）中就算他說可以reduce cost ，但是也沒有說減少的程度會低到比從礦中挖出來還低～

[小花]

為什麼A對呢?

[amazingslim]

題目:
1.鈾大部分從礦坑來
2.有可能從海中提煉，但售價不敷成本
3.直到成本降低，海中提煉法在商業上是不可行的(不賺錢)

(A)yes:如果地面上的產量快耗盡的話，只剩從海裡提煉了
no:如果地面上的產量沒有快耗盡的話，也就沒有動機從海裡提煉了

[小花]

感謝

難怪dibert8大牛說(A)提供了動機

[chris8888]

Most of the world's supply of uranium currently comes from mines.
鈾元素大部分世界的供應都是來自於採礦
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.
也可以從海水取得, 但是這樣做花費較高於從世界市場上取得
Therefore, until the cost of extracting uranium from seawater can somehow be reduced, this method of obtaining uranium is unlikely to be commercially viable.
因此, 直到從海水萃取的成本能夠降低, 這樣的方法才可能被商業化

總結 : 嫌透過海水取得很貴, 所以繼續要透過在世界市場上交易鈾元素

Which of the following would it be most useful to determine in evaluating the argument?
AE題 : 評估性題型

(A) Whether the uranium in deposits on land is rapidly being depleted
是否在陸地上的礦脈儲存量正快速地被耗竭?
正確 : 因為如果在陸地上的鈾元素存量正快速被耗竭, 那麼終將有一天在世界的市場上將無法在買得到這種鈾元素, 勢必一定要自己透過海水淬取鈾元素
(main argument : 嫌透過海水取得很貴, 所以繼續要透過在世界市場上交易鈾元素)
(B) Whether most uranium is used near where it is mined
靠近礦場, 無關
(main argument : 嫌透過海水取得很貴, 所以繼續要透過在世界市場上交易鈾元素)
(C) Whether there are any technological advances that show promise of reducing the cost of extracting uranium from seawater
是否有從海水萃取鈾元素的成本降低的希望這類的技術存在?
此為迷惑選項, 技術的存在與否是否可以降低成本? 可以降低到比在陸地上取得還要便宜ㄇ? 選項C都沒有說, 只說會降低成本, 假若在世界市場上買鈾元素一公斤100萬美元, 透過海水淬取投資成本機具以及人事費用危安保險金等等每公斤鈾元素要價170萬美元, 都沒有說出誰貴誰便宜? 這選項不好.
技術上的選項若要對的話, 必須要加上其他因子, 比方說本題要加上無法透過全球market取得低於此技術所提供的更低成本的鈾元素, 那這樣就很可能是對的了, 但是他沒說, 它只說可以降低成本, 到什麼地步與世界市場的關連性也沒有提及或是暗示.
另外, 光是技術層次的問題就要推翻或是支持選項, 通常不是正確選項.
(main argument : 嫌透過海水取得很貴, 所以繼續要透過在世界市場上交易鈾元素)
(D) Whether the total amount of uranium in seawater is significantly greater than the total amount of uranium on land
海水的存量和陸地的存量來比較, 不是重點
(main argument : 嫌透過海水取得很貴, 所以繼續要透過在世界市場上交易鈾元素)
(E) Whether uranium can be extracted from freshwater at a cost similar to the cost of extracting it from seawater
淡水海水不是重點, 無關
(main argument : 嫌透過海水取得很貴, 所以繼續要透過在世界市場上交易鈾元素)

[rola1225]

我覺得以現在的實事來看，A選項就容易了解了
現在不是油價一直漲嗎，如果一個東西 is rapidly being depleted ，那他的市價會上漲
上漲的程度一定會 greater than the price on the world market
所以其實A選項也有考慮成本