单项选择题
A.孔外微差、V字型起爆 B.孔外延期、排间微差 C.孔内延期、排间微差
A.10% B.6% C.4%
A.0.5cm,1cm B.1cm,0.5cm C.1.5cm,1cm
A.≥30MPa/m B.≥40MPa/m C.≥60MPa/m
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