新PREP PART2 82

dengyichao

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.

B. The reduction in the cost of solar-power equipment has occurred despite increased raw material costs for that equipment.

C. Technological changes have increased the efficiency of oil-fired power plants.

D. Most electricity is generated by coal-fired or nuclear, rather than oil-fired, power plants.

E. When the price of oil increases, reserves of oil not previously worth exploiting become economically viable.
这题就没看懂，the threshold of economic viability的概念也没搞清楚，哪位给解释一下。17号就考试了，紧张啊。。。

tracyforever

扎一看，我也没看明白，后来google了一下，知道了。

题目的意思是这样的：当每桶油的价格上涨到一定数额，即35美金(the threshold)，新的太阳能发电厂就比传统的烧油的发电厂更有效率。

而题目说the threshold of economic viability一直都没有改变，就是说在油的价格上涨的同时，传统的电厂在工艺技术上也更加先进。对油的消耗在减少，所以总共的临界值还是没有变。

个人理解，仅供参考！

oranrona

那A为社么不对？顶~请赐教！