单项选择题
A.152 B.90 C.72 D.20 E.2
A.350/400=87.5% B.300/400=75.0% C.100/400=25.0% D.100/300=33.3% E.50/400=12.5%
A.0.104 B.0.075 C.0.143 D.用该资料不能计算 E.以上答案均不是