97免费在线观看视频,亚洲综合自拍网,黄色毛片免费观看,热久久综合网,免费看日产一区二区三区狠狠操av,久久久涩涩涩,在线精品免费视频,人人插天天干,久久91精品国产91久久

<pre id="xb0ya"><strong id="xb0ya"></strong></pre>

單項(xiàng)選擇題

Due to the hazards involved with Halon extinguishers on a ship，the size II extinguisher may only be used（）.

A.outside
B.on class C fires
C.in an emergency
D.on class B fires

你可能感興趣的試題

單項(xiàng)選擇題

Dry chemical fire extinguishers are effective on which type(s) of fire?（）

A.Burning oil
B.Electrical
C.Paint
D.All of the above

單項(xiàng)選擇題

Dry chemical extinguishers extinguish class B fires to the greatest extent by（）.

A.cooling
B.smothering
C.oxygen dilution
D.breaking the chain reaction

<ins id="0core"></ins>

<pre id="0core"><strong id="0core"></strong></pre>

<ruby id="0core"><output id="0core"><ruby id="0core"></ruby></output></ruby>