No sooner _______ than they began to work.(A)they No sooner _______ than they began to work.(A)they had arrived(B)they would a 分类:平顶山学院-大学英语4(高起本) 题型:选择题 查看答案
三相全控桥式整流电路带大电感负载时,控制角α的有效移相范围是( )。 三相全控桥式整流电路带大电感负载时,控制角α的有效移相范围是( )。 A.0°-90°B.30°-120°C.60°-150°D.60°-150° 分类:平顶山学院-大学英语4(高起本) 题型:选择题 查看答案