3) ha do vapor aod gases differ?

Your question, I guess, How do vapour and gases differ...

1.) Vapour is the changed state of any liquid either due to boiling or evaporation

2.) Vapour are more energetic as they have absorbed the latent heat of vaporization whereas Gases are low in energy because they are already in gaseous form at room temperature.

3.) Vapour have boiling points above room temperature while gases have their boiling point below room temperature.

no, the red giant is the hottest with 2.00.000.000 degrees celsius. while the white dwarf only 25,000 degrees celsius.