The question does not make sense. Air is compressible. It does not matter the speed. Please restate the question and provide more details so that we can understand what you want answered.
No, hot air balloons are kept up in the air by buoyancy, the same thing that keeps helium balloons up in the air, or that keeps ships afloat. The hot air in the balloon is less dense than the...
Well, Air Fresheners let off CFC's(Chloroflurocarbons) which once are released into the atmosphere are very hard to break down. CFC's deteriorate the Ozone layer, which is our protection from the...