- 搜標(biāo)題
- 搜題干
- 搜選項(xiàng)
單項(xiàng)選擇題
對(duì)于碳素鋼，當(dāng)含碳量（）稱(chēng)為低碳鋼.
A.≤0.20
B.≤0.25
C.≤0.30
A.≤0.20
B.≤0.25
C.≤0.30
