单项选择题
A.4.2% B.3.2% C.5.3% D.3.6% E.3.4%
A.51.9%~66.0% B.50.8%~67.2% C.49.2%~68.8% D.48.6%~69.4% E.52.3%~65.6%
A.为了分组 B.使资料条理化 C.检查核对资料 D.便于统计分析 E.使资料系统化