When a .22-caliber rifle is fired, the expanding gas from the burning gunpowder creates a pressure behind the bullet. This pressure causes the force that pushes the bullet through the barrel. The barrel has a length of 0.60 m and an opening whose radius is 2.8 10-3 m. A bullet (mass = 2.7 10-3 kg) has a speed of 380 m/s after passing through this barrel. Ignore friction and determine the average pressure of the expanding gas.