单项选择题
If emergency welding repairs must be made to the upper area of a fuel tank, the tank and/or adjacent compartments may need to be （）
A.gas freed B.inerted C.filled with water D.all of the above as necessary
单项选择题 Which of the following statements is least likely to cause the ignition of fuel vapors?（）
单项选择题 A burning AC motor would be considered what class of fire?（）
单项选择题 Fire dampers prevent the fire spreading through the process of （）.
