单项选择题
A.斗型 B.平底 C.方孔 D.三种均可
A.0.1mg/L~0.8mg/L B.0.02mg/L~0.8mg/L C.0.2mg/L~0.8mg/L D.0.02mg/L~0.2mg/L
A.0.05mg/L~4mg/L B.0.3mg/L~4mg/L C.0.05mg/L~0.3mg/L D.0.3mg/L~3mg/L