（）的顶棚、墙面和地面均应采用A级装修材料。
A．无自然采光楼梯间
B．封闭楼梯间
C．采光楼梯间
D．防烟楼梯间
E．电梯间
参考答案：A, B, D
------ What did he want to know, Jim?
-------_________ I could finish writing the report.
A．When was it
B．It was when that
C．It was when
D．When it was that
自动扶梯工作制动器其控制至少应有（）套独立的电气装置来实现。
A.一；
B.两；
C.三；
