Place a beaker inside a bath filled with water so that the beaker is about ½ filled with water and the other ½ air. (you might have to let some air out by tilting the beaker.)

Add water to the bath.

a.) What happens to the water level inside the beaker?

b.) Has any air escaped the beaker? Has the amount of air inside the beaker changed?

c.) What happens to the density of the air inside the beaker when you add the water?