用话音信号调制SSB发信机时,应调制:()
A、末级功放
B、前制功放
C、第一搬频电路
D、第二搬频功放
参考答案:C
Mr. Smith was the only one of those who ________ to the dinner.
A.were invited
B.were inviting
C.was inviting
D.was invited
多层悬挑式按落地式脚手架的要求搭设。()