单选题 {{B}}Passage 3{{/B}}

All the useful energy at the surface of the earth comes from the activity of the sun. The sun heats and feeds creatures and mankind. Each year it provides men with two hundred million tons of grain and nearly ten million tons of wood, coal, oil, natural gas, and all other fuels are stored energy from the sun. (80) {{U}}Some was collected by this season's plants as carbon compounds. Some was stored by plants and trees ages ago. {{/U}}Even waterpower derives from the sun. Water turned into vapor by the sun fails as rain. It courses down the mountains and is converted to electric power. Light transmits only the energy that comes from the sun's outer layer, and much of this energy that is directed towards the earth never arrives. About nine tenths of it is absorbed by the atmosphere of the earth. In fact, the earth itself gets only one half millionth of the sun's entire output of radiant energy.

单选题 The sun is the source of all of the following EXCEPT ______

【正确答案】 C

【答案解析】[解析] 事实细节题。文章前半部分提到地球上所有的能量来源都离不开太阳，比如地球上的一切动植物，人类，树木，煤矿，石油，天然气，其他燃料等，但是没有提到C“原子能”，所以选C。

单选题 Radiant energy is stored as carbon compounds by ______

单选题 The sun's energy provides us with all EXCEPT ______

【正确答案】 B

【答案解析】[解析] 事实细节题。文中后半部分提到水能、雨水和光都是来自于太阳能。没有提到B“水鸭”，因此答案为B。

单选题 The largest part of the light energy directed towards the earth is ______

【正确答案】 B

【答案解析】[解析] 事实细节题。文中倒数第二句提到约有十分之九的太阳光被地球的大气层吸收了，真正到达的很少。

单选题 Of the sun's total output of radiant energy, the earth receives

【正确答案】 D

【答案解析】[解析] 事实细节题。文中最后一句说，事实上，地球只接收了太阳所有辐射能量的百万分之零点五，所以是相当小的一个比例。