单项选择题
Upon release to the atmosphere，LFG readily（）.
A.vaporizes B.attacks caustically C.rises D.attacks corrosively
单项选择题 To determine the pressure and temperature limitations under which LFG is required to be transported on a barge，you should look at the（）.
单项选择题 The weight of liquefied petroleum gas vapors as compared to air is（）.
单项选择题 The vapor pressure of a substance（）.
