自动扶梯适用于（）。
A.有大量人流上下的建筑物；
B.美观要求较高的建筑物；
C.大量乘客携带货物的建筑物；
D.有无障碍通道的建筑物
参考答案：A
— What great trouble I have solving this problem now！
—_____ my advice, you ________less trouble.
A．If you had taken, would have had
B．If you took, would have
C．If you had taken, would have
D．If you take, will have
500kV变压器进行真空注油前，其真空保持时间为（）小时。
A.不少于8h
B.不少于12h
C.不少于24h
D.不少于36h
