A rigid, insulated tank contains 0.6 kg of air, initially at 200 kPa, 20°C. The air is stirred by a paddle wheel until it's pressure is 250 kPa. Determine the (a) work in kJ, (b) the change in exergy of the air in kJ, and (c) the amount of exergy destroyed, in kJ. Kinetic and potential energy effects can be ignored and the dead state is To= 20°C, Po =100 kPa.