直流母线电压不能超过额定电压的()变化范围
A.正、负10%
B.正、负2%
C.正、负5%
参考答案:A
--- Did you have a wonderful time at the ball last night?
--- __________! I’ve never had a more wonderful time all my life.
A.You bet
B.No problem
C.Don’t mention it
D.That’s right
铁塔工程的基础部分材料的检验必须实行()制度,监理员现场进行检查、确认、见证、取样,包括施工设备、钢筋、水泥、木材、砂石等主要材料。
A.进场检验
B.材料报验
C.抽查检验
D.逐个检验