How many energy levels does this atom have

If anyone would be able to me out with these three questions it would be these are from the chem 2202 course.

Butane gas reacts with oxygen gas to give carbon dioxide gas and water vapor (gas). if you mix butane and oxygen in the correct stoichiometric ratio, and if the total pressure of the mixture is 390 mmhg, what is the pressure (in mmhg) of water vapor after the reaction is completed (temperature and volume do not change).

Which of these are physical changes in matter? check all that apply boiling water a pencil being sharpened exploding dynamite freezing water rotting cheese