單項(xiàng)選擇題
A.760 B.845 C.600 D.925
A.平爐 B.轉(zhuǎn)爐和大型平爐 C.電爐 D.什么爐型均可
A.S≤0.055%P≤0.055% B.S≤0.045%P≤0.045% C.S≤0.055%P≤0.045% D.S≤0.55%P≤0.45%