对于集合A={2,4,6},若a∈A,则6-a∈A,那么a的值是( )。
2或4
My sister wanted to know where________going. [ ]
A. I am
B. was I
C. I was
D. are you
变配电室的设备验收分为()验收和检修调试验收两类
A.安装交接
B.资料
C.发电
D.电气试验