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 its pressure is 250 kPa. Using the ideal gas model with Cv = 0.72 kJ/(kg*K), determine, in kJ, (a) the work, (b) the change in exergy of air, and (c) the amount of exergy destroyed. Ignore the effects of motion and gravity, and let To = 20 C, Po = 100 kPa.