99色精品-9色在线-99色在线-99色视频 国产欧美日产一区二区三区_亚洲精品亚洲人成在线观看_四虎在线精品永久观看_免费一级a一片久久精

單項(xiàng)選擇題

The four basic components of a fire are fuel, heat, oxygen and a chain reactionWhich of the following statements best describes what must be eliminated to extinguish a fire?()

A.Any one component can be eliminated to extinguish a fire
B.Any two components must be eliminated to properly extinguish a fire
C.Any three components must be eliminated to properly extinguish a fire
D.Ali four components must be eliminated to extinguish any fire

微信掃碼免費(fèi)搜題