If a television or radio breaks the new

—Ted found a policeman passing by and handed the mobile phone over to him.

—But he _________ at the place until the owner returned.

A．must have waited

B．might have waited

C．would have waited

D．could have waited

0.53的计数单位是______，再加上______个这样的计数单位得到1．

下列关于钢材的说法错误的有（）。

A.钢材的结构自重轻，便于装配，易于拆卸

B.适用于中型工业厂房

C.可以采用螺栓和铆钉连接

D.钢材易锈蚀，需经常进行维护

E.钢材的耐火性好

滚动轴承配合当负荷方向不变时，转动圈应比固定圈的配合松一些。

毒性药品每次处方剂量不得超过

A．一日极量
B．二日极量
C．三日极量
D．一日剂量
E．二日剂量