B.O<A<B<C C.O<C<B<A D.B<A<C<O
A.碳素結(jié)構(gòu)鋼 B.優(yōu)質(zhì)碳素結(jié)構(gòu)鋼 C.碳素工具鋼 D.普通碳素鋼
A.27% B.小于1.5% C.大于1.5% D.等于1.5%
