非现场信息收集流程包括哪几个主要环节（）
A.信息采集
B.质量审核
C.情况记录
D.信息变更
参考答案：A, B, C, D
两带电小球，电荷量分别为＋q和－q，固定在一长度为l的绝缘细杆的两端，置于电场强度为E的匀强电场中．杆与场强方向平行，其位置如图所示．若此杆绕过O点垂直于杆的轴线转过180°，则在此转动过程中电场力做的功为( )
A．0
B．qEl
C．2qEl
D．πqEl
We the postcards yesterday, but it didn’t arrive.
A．should receive
B．ought to receive
C．ought to have received
D．must have received
