推 heystranger: 謝謝DONZ~ 11/23 15:03
※ 編輯: ndxica (1.34.44.231), 03/22/2016 11:28:08
※ 引述《heystranger (卍曠世巨魯霸氣登台卍)》之銘言：
: Electric utilities pay less for low-quality coal per ton delivered than for
: high-quality coal. Yet more low-quality coalthan high-quality coal must be
: burned to generate the same amount of electricity. Moreover, per ton of coal
: burned,low-quality coal generates more ash than does high-quality coal, and
: the disposal of ash is becoming more and more expensive.
: The considerations above, if true, most strongly support which of
: the following claims?
: (A) A coal-burning utility might not be assured of benefiting economically
: by always adhering to the policy of keeping its overall coal purchasing
: costs as low as possible.
: (B) In those regions where the cost of disposing of coal ash is negligible,
: it is more expensive for coal-burning utilities to use high-quality
: coal than low-quality coal.
: (C) Transportation costs represent a smaller proportion of the cost per
: delivered ton for low-quality coal than for high-quality coal.
: (D) It is no less expensive to dispose of a ton of coal ash that results
: from the burning of high-quality coal than it is to dispose of a ton of
: coal ash that results from the burning of low-quality coal.
: (E) In regions where coal-ash disposal is the least expensive, reserves of
: low-quality coal are likely to decline at a faster rate than are
: reserves of high-quality coal.
在處理 coal disposal 最便宜的 "地區"
並沒有翻轉題目的事實:
coal disposal cost: low quality coal > high quality coal
所以無法確認 low quality coal 是否會較快消耗
: ---------------------------------------------------------------------------
: 小弟資質愚鈍不解答案為何是A，這題做了快10分鐘...超難選擇答案最後選了E
: 再回過頭看A，我的理解A:購買低成本無法保證帶來經濟利益(不知道這大意對不對)
: 可是原文我找不到一個conclusion明確表明low quality就是不實用
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題目就是要請你推結論，當然不會明確寫出來
且此題考慮的並不完全是在討論實用性，而是以經濟效率來考慮
: 只有隱性的自己心裡認為這個low quality不實用，與其說support，我怎麼覺得這題更
: 像assumption? 請大大指教!
題目資訊： cost: low quality coal 有優勢
efficiency: high quality coal 有優勢
disposal of ash: high quality coal 有優勢
--> low quality 不見得有經濟上的優勢 (答案 (A))
我猜想你的疑點大概是，題目並沒有明確指出，
high quality coal 和 low quality coal 總成本的優劣
但按照寫作邏輯來看，先提出 low quality coal 的優勢
而後再提其劣勢，並舉出兩點，
當然自然而然得到答案 （A）- low quality coal 不見得有經濟優勢
且 (A) 的答案是相當保守，使用 "might"，
並沒有很武斷的說總成本會較高
這答案當然不是 assumption - assumption 在推理過程屬於"原因"的部分
而此題答案是需要題目條件來"支持"
這樣問吧，你自己覺得是題目 support 答案 (drawn conclusion)，
還是答案 (assumption) support 題目?
我想前者應該更符合一般思考的邏輯
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※ 編輯: ndxica (1.161.139.131), 11/23/2015 08:18:35