题目含碳量为()铸铁称为共晶白口铸铁。A. 0.02%B. 0.77%C. 2.11%D. 4.3%含碳量为()铸铁称为共晶白口铸铁。A. 0.02%B. 0.77%C. 2.11%D. 4.3%题目解答答案D. 4.3%