Air is initially at a temperature of 500 K and a pressure of 100 kPa. A process occurs so that the specific internal energy of the air increases by 200 kJ/kg (i.e. u2 - u1 = 200 kJ/kg). Modeling the air as an Ideal Gas, determine the final temperature assuming a) constant specific heat equal to the value at 300 K, b) constant specific heat equal to the value at the average temperature during the process, c) using third order polynomial expression table A-2c, d) variable specific heat by using properties on Table A-17.