【简答题】阅读下面短文,掌握其大意,从每题所给的A、B、C、D四个选项中,选出最佳选项, 并在答题卡上将该项涂黑。 Feeling hopeless and sick at heart, Tom turned away. For a quick moment his eyes met the eyes of the cook, and he saw there a 36 of such hatred and...
【单选题】Why should you wear a self-contained breathing apparatus before entering the engine room after the fixed CO2 system has been discharged to combat a major fine?
A.
Because carbon dioxide dilutes the oxygen concentration in the atmosphere and may cause as phyxiation.
B.
Because carbon dioxide breaks down in fire into carton monoxide which may cause blood poisoning in the person breathing this gas.
C.
Because carbon dioxide is a colorless and odorless gas that becomes highly toxic in the presence of high temperatures and will quickly incapacitate a person exposed to this gas.
D.
This action is unnecessary as carbon dioxide is neither poisonous nor toxic but is a relatively harmless gas.