下图是“大气热力作用关联示意图”，读图回答下列各题。近地面大_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题单项选择题案例分析题

下图是“大气热力作用关联示意图”，读图回答下列各题。

近地面大气的热量主要直接来自（）

A．a

B．b

C．c

D．d

答案

参考答案：D

解析：

根据所学的大气热力作用的原理可以判断出图中的abcd分别代表的太阳辐射、地面的长波辐射、大气辐射中的大气逆辐射和大气辐射中射向宇宙的部分。大气的主要的、直接的热量来源是地面的长波辐射，故选B。

单项选择题

轴流通风机的气体由( )进入。

A．集风器

B．叶轮

C．导叶

D．扩压器

完形填空

Robeson was born in a very poor family. At seven, he had to pick coal in a deserted mine near his home, then he sold   1  he had picked and earned a few coins to help his parents. He had   2  schooling, for being so poor, how could they   3  school fees?
When he was fifteen, he worked   4  a servant in a school. Looking at other children studying in the classroom, he felt   5  for himself. How he  6  to have the same chance! He decided to study by  7 . In the daytime, after the sweeping and cleaning was over, he   8  stand by the window outside the classroom trying to catch what the teacher said. At night, he tried his best to remember what he 9   during the day. He worked  10  hard at his lessons that he sometimes had just three or four hours to sleep. The more he learned, the greater   11  he showed in his lessons. A maths teacher discovered him and came to like this diligent boy and  12  him to sit at the back of the class. In one exam, he was the   13   one in the whole school who reached the highest grade. He would have been given the scholarship if he   14   a regular student of the school.
Robeson   15  through six long years with his study of maths and wrote several articles which captured the   16  of some university professors. They admired his talent   17  his diligence. To give him a good chance, they hired him as a librarian and   18   him free guidance. Robeson felt   19 , for he was sure that before him there was a broad road  20  success.

A．the teacher

C．his parents

D．his schoolmates

A．had learned

B．has been taught

D．had been written down

B．according to

D．in spite of

D．disappointed

B．coming from

D．covered with