题目

成语“釜底抽薪”包含着灭火的原理.下列灭火方法也依据这个原理的是( ) ①熄灭酒精灯时,用灯帽盖灭;②熄灭燃气灶火焰时,关闭阀门;③用嘴吹灭蜡烛;④森林着火时,将大火蔓延线路前的一片树木砍掉;⑤房屋着火时,用高压水枪灭火. A.①和②   B.②和③   C.②和④   D.①和⑤ 答案:【考点】灭火的原理和方法. 【专题】化学与能源. 【分析】釜底抽薪体现的是一种常用的灭火方法,它利用的原理是清除可燃物,将锅底的柴火抽走,就没有了可燃物,起到灭火的作用. 【解答】解:①灯帽盖灭酒精灯是隔绝空气灭火,与“釜底抽薪”灭火原理不同;②熄灭燃气灶火焰时,关闭阀图文对对碰。A. B. C. D. E. F. G. H. I. J. 【1】The T-shirt is 90 yuan. (_____)【2】Hold a lamb. (_____)【3】—What's this? —It's a goat. (_____)【4】The library is on the first floor. (_____)【5】There are four tomatoes. (_____)【6】It's windy. (_____)【7】It's time to go to school. (_____)【8】The dress is very pretty. (_____)【9】It's cool today. I can wear my jacket. (_____)【10】It's 9:30. It's time to go to bed. (_____)
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