电力载波一般通道的储备电平为()
A.6~9dB
B.4dB
C.9~13dB
D.20dB
参考答案:B
Is this hotel _____ you once stayed at? [ ]
A. the one
B. /
C. which
D. where
百色市重点开发区域有()
A.右江区
B.平果县
C.凌云县
D.田阳县