Danny is talking to the man beside ____________. [ ]
A. him
B. he
C. they
答案：A
I’ll give you y friend’s home address ______ I can be reached most evenings.
A．which
B．when
C．whom
D．where
比选器对信号进行优选，主要依据的参数是信噪比和（）。
A、噪声电平
B、信号电平
C、音量大小
D、距离
