dpb wrote:
....
Precisely...the air that leaves is simply a small fraction of the same
air that's already there. It doesn't "take" any disproportionate amount
of water vapor with it, only it's entrained share. Hence, the remaining
air (a _very_ tiny fraction less volume, perhaps) is still the same
moisture level.
....
That, of course, is mass, not volume--the volume is fixed only the
density decreases slightly owing to the postulated heating...

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