A.30% B.40% C.50% D.60%
A.18% B.20% C.21% D.30%
A.可燃?xì)獗ㄏ孪夼c爆炸上限的百分比 B.可燃?xì)怏w的爆炸下限值 C.環(huán)境中可燃?xì)獾暮空急ㄏ孪薜陌俜謹(jǐn)?shù) D.可燃?xì)庵醒鹾康陌俜謹(jǐn)?shù)