当警衔高的人民警察在职务上隶属于警衔低的人民警察时，警衔高的为上级。( )
参考答案：错
下列各式中正确的是 [ ]
A.（-a3）2=-a6
B.（2b-5）2=4b2-25
C.（a-b）（b-a）=-（a-b）2
D.a2+2a b+（-b）2=（a-b）2
_____I phoned the police, then I made a list of what had been stolen, and then I made myself a cup of tea.
A．At first
B．First
C．In the first place
D．At the start
