单项选择题
A.900 B.700 C.100 D.60
A.0.2-0.3m B.0.4-0.5m C.0.5-0.6m D.0.8-1.0m
A.焦炭 B.褐煤 C.烟煤 D.无烟煤
A.±1.0% B.±1.5% C.±2.0% D.±2.5%
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