【单选题】Employees would like to work under team leaders who good examples
【判断题】「勉強する」的非过去否定式为「勉強しない」。()
【单选题】数字万用表测二极管时,显示“.372”,说明二极管()
【单选题】已知两个正弦量为u1=20sin(314t +π/6)V,u2=40sin(314t-π/3)V, 则( )
【单选题】已知两个正弦量u1=20sin(314t+60°)V,u2=90sin(314t-30°)V,则____。