单项选择题
A.20;50 B.50;100 C.80;120 D.100;200
A.1.5% B.2% C.2.5% D.3%
A.15%~20%、25%~35% B.20%~30%、25%~35% C.8%~15%、15%~20% D.15%~20%、8%~15%