There is a noise that comes and goes in one of our bathrooms. I think it is air in the water line. Since yesterday it seems to be coming and going more often. How do I resolve this problem?

It's probably not air in your line but a adjustment in your toilet tank. Pull the lid and check the water level. It should be 1/2" under the top of the white overflow tube when the tank's filled. If not then lower the tanks water to the correct level. Good luck, Tom