The air-release flap on a hot-air balloon us used to release hot air from the balloon when appropriate. On one hot-air balloon, the air release opening has an area of 0.5 m2, and the filling opening has an area of 1 m2. During a two-minute adiabatic flight maneuver, hot air enters the balloon and 100 kPa and 35°C with a velocity of 2 m/s; the air in the balloon remains at 100 kPa and 35 °C; and air leaves the balloon through the air-release flap at velocity 1 m/s. At the start of this maneuver, the volume of the balloon is 75 m3. Determine the final volume of the balloon and work produced by the air inside the balloon as it expands the balloon skin.