Re: [CR. ] pp08 cr2-82

看板GMAT (GMAT入學考試)作者Merica (美加文教)時間15年前 (2011/06/03 12:02)推噓0(0推 0噓 0→)

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"threshold意為門檻。此題的重點在於比較 "solar power plants"和 "oil-fired power plants"的 "efficiency"，請注意比的是「整個 "plants"」的 "efficiency"， (A)所說的 "cost of oil"只是整個「整個 "plants"」成本中之一部分，考慮的不夠完整， (C)說的就是 "efficiency of oil-fired power 「plants」"，所以(C)才對。另外，此題是蠻舊的GRE考題，每桶原油35元大概是1980年代的事了。（以上內容由美加黃冠文老師提供） ※ 引述《cindy0416 (ptt)》之銘言： : Technological improvements and reduced equipment costs have made converting : solar energy directly into electricity far more cost-efficient in the last : decade. However, the threshold of economic viability for solar power (that : is, the price per barrel to which oil would have to rise in order for new : solar power plants to be more economical than new oil-fired power plants) is : unchanged at thirty-five dollars. : Which of the following, if true, does most to help explain why the increased : cost-efficiency of solar power has not decreased its threshold of economic : viability? : A. The cost of oil has fallen dramatically. : C. Technological changes have increased the efficiency of oil-fired power : plants. : 答案是C，請問A為何不對呢？ : A和C在我看來都是差不多的。像C，就算效率提高，但油價仍然高漲的話，火力 : 發電還是很貴，太陽能電仍然有其效益。而A，則是油價提高，但不知道效率如 : 何。所以A和C似乎都不完整。 : 還是是我誤解了 "threshold of economic viability"的意思？ -- ▅▅▅▅ ▅▅ ▅▅▅ ▅ ▅▅ ▅▅▅ █ █ █ █▅ █▄█ ▄ █ █▄█ █ █ █ █▄ █◥▅ █ █▅ █ █ 7/2(六)下午2：00美加文教新制GRE&字彙免費講座莫清崴博士/江璞教授主講歡迎蒞臨 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 114.36.49.125