※ 引述《heystranger (卍旷世巨鲁霸气登台卍)》之铭言： : 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. 在处理 coal disposal 最便宜的 "地区" 并没有翻转题目的事实: coal disposal cost: low quality coal > high quality coal 所以无法确认 low quality coal 是否会较快消耗 : --------------------------------------------------------------------------- : 小弟资质愚钝不解答案为何是A，这题做了快10分钟...超难选择答案最後选了E : 再回过头看A，我的理解A:购买低成本无法保证带来经济利益(不知道这大意对不对) : 可是原文我找不到一个conclusion明确表明low quality就是不实用 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 题目就是要请你推结论，当然不会明确写出来 且此题考虑的并不完全是在讨论实用性，而是以经济效率来考虑 : 只有隐性的自己心里认为这个low quality不实用，与其说support，我怎麽觉得这题更 : 像assumption? 请大大指教! 题目资讯： cost: low quality coal 有优势 efficiency: high quality coal 有优势 disposal of ash: high quality coal 有优势 --> low quality 不见得有经济上的优势 (答案 (A)) 我猜想你的疑点大概是，题目并没有明确指出， high quality coal 和 low quality coal 总成本的优劣 但按照写作逻辑来看，先提出 low quality coal 的优势 而後再提其劣势，并举出两点， 当然自然而然得到答案 （A）- low quality coal 不见得有经济优势 且 (A) 的答案是相当保守，使用 "might"， 并没有很武断的说总成本会较高 这答案当然不是 assumption - assumption 在推理过程属於"原因"的部分 而此题答案是需要题目条件来"支持" 这样问吧，你自己觉得是题目 support 答案 (drawn conclusion)， 还是答案 (assumption) support 题目? 我想前者应该更符合一般思考的逻辑 -- Donz 2015 12月全科机经班: http://goo.gl/VwO4yJ Donz + Keewee 速成实力寒假班: http://ndxica.pixnet.net/blog/post/40937209 Donz GMAT FB: https://www.facebook.com/groups/DonzGMAT --

※ 发信站: 批踢踢实业坊(ptt.cc), 来自: 1.161.139.131 ※ 文章网址: https://webptt.com/cn.aspx?n=bbs/GMAT/M.1448237556.A.A91.html ※ 编辑: ndxica (1.161.139.131), 11/23/2015 08:18:35 ※ 编辑: ndxica (1.34.44.231), 03/22/2016 11:28:08