[求助] 大全17-14，16 急救！

sandrachen

14.   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.（C）

(E) When the price of oil increases, reserves of oil not previously worth exploiting become economically viable.

括号的那句看不懂意思：（，，请牛人帮忙翻译一下

16.   The proportion of women among students enrolled in higher education programs has increased over the past decades. This is partly shown by the fact that in 1959, only 11 percent of the women between twenty and twenty-one were enrolled in college, while in 1981, 30 percent of the women between twenty and twenty-one were enrolled in college.

To evaluate the argument above, it would be most useful to compare 1959 and 1981 with regard to which of the following characteristics?

(A) The percentage of women between twenty and twenty-one who were not enrolled in college

(B) The percentage of women between twenty and twenty-five who graduated from college

(C) The percentage of women who, after attending college, entered highly paid professions

(D) The percentage of men between twenty and twenty-one who were enrolled in college（D）

(E) The percentage of men who graduated from high school

答案虽然做出来了，但是想不明白为什么

ll_zl

17-14

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

对于太阳能的经济可行性的起点是每桶油35$,（在价格上升到某个程度，新太阳能工厂就比oil-fired工厂更经济了）

大致意思是：当每桶油是35$以下的时候，oil-fired工厂更经济；超过这个价格，就是太阳能工厂更经济了