What would you like? [ ]
A. I'd like some beef.
B. Let me try.
C. Help yourself.
答案:A
水深1.5m以内、流速50Cm/s以内、河床土质渗透系数较小时可筑()围堰。
A.土
B.石
C.土袋
D.混凝士
电费违约金、违约使用电费、罚款的概念和区别是什么?