阅读理解。

     This is a picture .In the picture you can see some hills (小山), trees and a school. You can see some boys and girls.

They are at school. The school is HongXing Middle School.   Lingling is twelve.  Fangfang is twelve, too. They are in

the same class. They are good friends. Miss Gao is their teacher.

1. _________is Fangfang and Lingling's teacher.

A. Miss Wang    

B. Miss Gao  

C. Mr Smith      

D. Mr Gao

2. The boys and girls are________________ .

A. at school      

B. at home  

C. behind the hill  

D. under a tree

3. Lingling and Fangfang are_____________.

A. in different classes    

B. in different grades    

C. eleven      

D. good friends

4. They're in_____________ 

A. HongXing Middle School    

B. hongxing middle school

C.HongXing school          

D. Hongxing middle school

5. The hills ,trees, the school and the students are _________ .   

A. in a book      

B. on the blackboard  

C. in a picture        

D. in the wall

已知同温同压下，气体体积比等于分子数比。现有aLH₂与CO的混合气体，完全燃烧后用去LO₂，则H₂与CO混合气体中，两种气体的体积比是 [ ]

A．2：1

B．1：1

C．1：2

D．任意比