单项选择题
A.variable B.the same C.lighter D.heavier
The vapor pressure of a substance（）.A.decreases as temp...
单项选择题The vapor pressure of a substance（）.
A.decreases as temperature increases B.increases with the temperature C.is not affected by temperature D.may increase or decrease as the temperature rises
The vapor pressure of a gas is the pressure necessary t...
单项选择题The vapor pressure of a gas is the pressure necessary to keep it in a(n)（）.
A.soluble state B.solid state C.liquefied state D.inert state
The tops of vents from gasoline tanks should terminate（...
单项选择题The tops of vents from gasoline tanks should terminate（）.
A.in open air B.inside cabins C.in machinery space D.underwater
