单项选择题
A.麻面B.凹坑C.凸块D.裂纹
A.5-10mmB.6-20mmC.5.5-30mmD.5-40mm
A.≤0.50B.≤0.40C.≤0.30D.≤0.20
A.950B.900C.830D.785
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