单项选择题
A.20000m3B.30000m3C.2000m3D.150m3
A.≤100MPa/minB.≥200MPa/minC.100MPa/minD.200MPa/min
A.25HRCB.251HBC.20HRCD.241HB
A.0.50%B.0.60%C.0.70%D.0.80%
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