In one of the previous lectures, we considered the process of charging a helium tank. Let us use the exergy analysis to calculate the minimum required energy consumption for various steps of the process. The volume of the tank is 10 Liters. The environment is at 100 kPa and 300 K. (a) First, calculate the minimum amount of work necessary to create a vacuum in the tank. Is it equal to the exergy of the vacuum inside the tank? (Answer: 1kJ) (b) Second, find the exergy of a fully charged helium tank. Assume that in the fully charged state, the gas is at an absolute pressure of 10 MPa (100 atmospheres) and a temperature of 300 K. Treat helium as an ideal gas. (Answer: 361.5 kJ)