航海英語(yǔ)液化氣體與IGC規(guī)則單項(xiàng)選擇題每日一練(2019.07.27)

來(lái)源：考試資料網(wǎng)

1 The weight of liquefied petroleum gas vapors as compared to air is（）.

2 On a hydrocarbon flammability chart the line which extends from 0% to 21.8% oxygen，lying tangent to the flammability range，is called the（）.

3 After the initial cleaning of flue gas in an inert gas system the gas is passed through what device for final cleaning?（）.

4 One of the principal dangers inherent in liquefied petroleum gas is（）.

5 Compared to the amount of concentrated foam liquid used，the amount of low expansion mechanical foam produced is（）.