Sajmon

I don't know to solve this homework and i need a little help Diver at a depth of 20 m below the water breaths 1 liter of air. With what acceleration the air bubble begins to move against the surface ,how his speed varies with time and what is its volume at a depth of 5 m? The water temperature is 20 ° C. Part of a solution will be need to find numerically. Thanks in advance