单项选择题
A.0.6%~0.8%B.0.4%~0.6%C.0.2%~0.4%
A.0.1%~0.7%B.0.2%~0.8%C.0.3%~0.9%
A.自供热转炉炼钢B.空气转炉炼钢C.顶底复吹转炉炼钢