单项选择题
A.贫煤、瘦煤、焦煤、肥煤、气煤、不粘煤及长焰煤 B.贫煤、瘦煤、焦煤、肥煤、气煤、弱粘煤、不粘煤及长焰煤 C.贫煤、瘦煤、焦煤、肥煤、气煤 D.瘦煤、焦煤、肥煤、气煤、不粘煤
A.0-10% B.0-15% C.0-20% D.0-25%
A.5-10% B.10-20% C.15-20% D.15-25%