单项选择题
A.刚采出煤样B.制备好煤样C.化验时煤样D.备查煤样
A.100B.90-105C.105-110D.100-110
A.3B.4C.5D.6
A.1.3-1.4B.1.4-1.5C.1.5-1.6D.1.3-1.6
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