A．利用电池外壳的金属材料 B．防止电池中汞、镉和铅等重金属离子对土壤和水源的污

阅读短文，判断正“√”误“×”。

Visitor (旅客): Excuse me. How can I get to Beijing Library?

Girl: Take (乘) Bus No.320 and get off (下车) at the third stop (站). Then turn right at the first

       crossing (交叉路口). The library is on your left.

Visitor: Thanks very much.

Girl: You're welcome!

( ) 1. The visitor is going to Beijing Library.

( ) 2. He can take Bus No.320 and get off at the second (第二) stop.

( ) 3. He must (必须) turn right at the first crossing.

( ) 4. Beijing Library is on his left.

过境动物的尸体、排泄物、铺垫材料以及其他废弃物，不得擅自抛弃。( )

引起副溶血性弧菌食物中毒的好发食品是（）

A.奶制品

B.海产品

C.豆制品

D.剩饭

E.肉制品

牙买加国际货币体系的运行机制包括哪些主要内容？

频域资源调度的最重要的依据是（）

A.CQI

B.UE能力

C.系统带宽

D.缓存数据量