A small auxiliary power device is designed as shown in the schematic. Nitrogen is contained at 14 MPa and 20ºC in the tank which is connected through a valve to an adiabatic turbine which drives an electric generator. The power output of the generator is to be 75 W, and the pressure at point 1 is maintained constant at 700kPa by a pressure regulator which operates as a throttling device. The nitrogen exhausts from the turbine at 100 kPa. What size volume tank is necessary to produce the power output for a period of one hour? Assume the tank remains isothermal at 20ºC and that power production ceases when the tank pressure reaches 700 kPa. Use constant specific heats at room temperature. For the turbine process use the relation: where k is the specific heat ratio and state 2 is the turbine exit.