容量为32的样本,若某组样本频率为0.25,则该组的频数为( )
A.14
B.8
C.16
D.无法确定
该组样本的频数为32×0.25=8
则该组的频数为8.
故选B.
He __________ his aunt’s when he went to Wuhan on business.
A.called on
B.called at
C.dropped in on
D.dropped in
关于脑脓肿(如图所示)下面哪项说法不正确()
A.如在脑脓肿的脓汁中查细菌一定能查到
B.先心病患者可并发脑脓肿
C.耳源性脑脓肿约2/3发生于患耳同侧颞叶
D.脑脓肿的致病菌以金葡萄为常见
E.血液性脑脓肿以额叶、顶叶为多见