4. Hydrostatics A novice scuba diver takes enough air from his tank to fully expand the lungs while he is at a certain depth H, and then holds his breath without exhaling, while rapidly swimming to the surface. This novice diver has not yet followed the PADI lessons in which they repeatedly emphasize that the one thing to do while diving is \"never ever hold your breath, always keep breathing\". Have up ever wonder why? Sure if you have ever taking a diving course. If the diver was at a depth of H=10 m when he inhaled and lled his lungs with a certain volume of air, what would the difference in pressure between the diver lungs and the exterior ambient pressure as he reached the surface? Comment on the risk of ascending without releasing the air. If instead of lungs surrounded by a rib-cage we simplify the problem into a balloon made of a elastic material that can expand or contract without breaking. If the balloon is inated at a depth of 10 meters under water with air at T=20 C from an air tank and to a certain volume, and then the balloon ascends to the surface with that same mass of air inside what is the percent change of volume of the balloon