When fueling has been completed（）. the fuel tank fill pipe should be left open to allow vapors to vent from the tank。 the engine should be started immediately to prevent vapor lock in the fuel line。 all hatches should be opened and all compartments should be ventilated。 open the fuel line and drain a small amount of gasoline into the bilge to clear the line of sediment。
要将整个桌面内容存入剪贴板中，应按（）键。 PrtSc。 Ctrl+PrtSc。 Alt+PrtSc。 Art+C。
An oxygen indicator will detect （）. concentrations of explosive gas。 an oxygen deficiency in a space。 the presence of harmful amounts of carbon monoxide。 All of the above。
结构钢焊接时，焊条选择的原则是焊缝与母材在哪方面相同（） 化学成分。 结晶组织。 强度等级。 抗腐蚀性。
The term "oily mixture", as defined in the Pollution Prevention Regulations includes （）. sludge。 oily ballast water。 bilge slops。 All of the above。
When fighting fires in spaces containing bottles of LPG (liquefied petroleum gas)，you should （）.
