单项选择题
A.6°、0.025gB.7°、0.10(0.15)gC.8°、0.20(0.30)gD.9°、0.40g
A.一类、一亚类B.二类、二亚类C.三类、一亚类D.四类、二亚类
A.一组B.二组C.三组D.四组