自动断路器跳闸或熔断器烧断后,应()再恢复使用,不允许试送电。
参考答案:查明原因
A.磁感线从磁体N极出发,终止于磁体S极
B.磁感线可以表示磁场的强弱与方向
C.磁感线上某点切线方向即为该点通电导线的受力方向
D.沿磁感线方向,磁场减弱
执行下列程序后,鼠标单击窗体,输出结果为______。 Private Sub Form_Click() Print"Click": End Sub Private Sub Form_MouseDown(Button As Integer,Shift As Integer,X As Single,Y As Single) Print"Down" End Sub Private Sub Form_MouseUp(Button As Integer,Shift As Integer,X As Single,Y As Single) Print "Up" End Sub
A) DownUpClick B) ClickDownUpC) DownClickUp D) UpDownClick