单项选择题
A.2% B.3% C.4% D.5%
A.1.0m B.1.2m C.1.5m D.1.8m
A.8 B.12 C.24 D.36
A.1.0 B.0.5 C.1.5 D.20
A.5 B.10 C.15 D.20
A.3kg B.1kg C.5kg D.2kg
A.6 B.10 C.16 D.20