起货设备中金属铸造的滑轮出现下列情况（）时应报废。A、裂纹 B

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起货设备中金属铸造的滑轮出现下列情况（）时应报废。

A、裂纹

B、轮槽壁厚磨损达原尺寸的20%

C、轮槽不均匀磨损达3mm，因磨损使轮槽底部内径减少量达绳径的50%

D、其它有损坏钢丝的缺陷时

答案

参考答案：A, B, C, D

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取等质量的镁、铝、锌三种金属分别与稀硫酸完全反应，下列图象中，能正确表示消耗的金属的质量（xg ）与产生氢气的质量（yg ）之间的关系是 [ ]

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