If I________ you,I would ask him to stay. [ ]
A. was
B. would be
C. were
D. am
答案:C
砼立方体劈裂抗拉强度试验中,与试件成型顶面垂直的面有()。
A、试件承压面
B、试验机压板面
C、试件底面
D、试件劈裂面
全数字电力线载波机音频通常有哪几种接口供选用?应用这些接口时,载波机的设置主要注意哪几点?