At steady state, air at 200 kPa, 325 K, and mass flow rate of 0.5 kg/s enters an insulated duct having differing inlet and exit cross sectional areas. The inlet cross sectional area is 6 cm squared. At the duct exit, the pressure of the air is 100 kPa and the velocity is 250 m/s. Neglecting potential energy effects and modeling air as an ideal gas with constant cp=1.008 kJ/kgK, determine:
a) velocity of air at inlet
b) temperature of air at the exit
c) the exit cross-sectional area