变压器二次带负载进行变换绕组分接的调压,称为()。
A、无励磁调压
B、有载调压
C、常用调压
D、无载调压
参考答案:B
They invented me to their party, ______ is kind of them. [ ]
A. this
B. that
C. which
D. as
对反复发作性心悸、胸闷伴黑矇患者,明确病因的首选检查应是
A.24小时动态心电图检查
B.心脏放射性核素检查
C.心血管造影
D.胸部X线片
E.心脏彩超