生物滤池装满（），能截留污水中悬浮物，胶体或溶解物，形成生物膜。
A.曝气器
B.填料
C.布水器
D.搅拌机
参考答案：B
回答下列问题.
1. Where's the hospital?
____________________________
2. Why do you like koala bears?
3. What language does Jim speak?
4. What size pizza would you like?
5. What's your address?
6. What does she do?
7. Do you want to be a bank clerk?
8. What did you do over the vacation?
结算风险保证基金即清算交割准备金。( )
