单项选择题
A．3% B．0.3% C．0.3/1 D．3‰
A．热拔合金钢制无缝锅炉管 B．热拔合金钢制无缝锅炉管HOT FINISHED SEAMLESS STEEL PIPES FOR BUILER C．热拔合金钢制无缝锅炉管787×39×5000-7000MM D．热拔合金钢制无缝锅炉管787×39×5000-7000MM HS 73045910
A．3% B．3‰ C．3/1 D．502/3/1
