A.550N/mm2 B.540N/mm2 C.650N/mm2 D.500N/mm2
A.60t B.40t C.30t D.20t
A.熱軋帶肋鋼筋 B.低碳鋼熱軋圓盤條 C.熱軋光圓鋼筋 D.冷軋帶肋鋼筋