某医生随机抽取100名儿童,检测粪便蛔虫阳性率,得阳性率为20%,此阳性率的标准误为()
A.4%
B.0.4%
C.0.04%
D.0.2%
E.1.6%
参考答案:A
When they broke open the door, they found a strange man lied on the floor unconscious.
A.lay
B.laid
C.lain
D.lying
发泡陶瓷保温板的施工操作中,挤塑板安装的表面平整偏差如何解决()
A.用2m托线板检查
B.用方尺和塞尺检查
C.用2m靠尺和塞尺检查
D.用直尺和塞尺检查