1. The problem statement, all variables and given/known data The human lungs can function satisfactorily up to a limit where the pressure difference between the outside and inside of the lungs is 1/21 of an atmosphere. If a diver uses a snorkel for breathing, how far below the water can she swim? Assume the diver is in salt water whose density is 1042 kg/m3. 2. Relevant equations 3. The attempt at a solution I think pgh, where p is density, g is gravitational acceleration, and h would be the height. I think the height would tell you how far the swimmer could go below water. I'm honestly not exactly sure where to start this one!