Air is flowing into a constant-area duct with the static pressure equal to 19.45 psia, the stagnation pressure equal to 20 psia, and the stagnation temperature equal to 60F. Heat is added to the flow at a rate of 190.8 BTU/lbm. Neglect the effects of friction. a.) What are the Mach Number, static pressure, stagnation pressure, and stagnation temperature at the duct exit? (psia, F) b.) How much heat transfer to the air would be required to choke the flow at the duct exit? (BTU/lbm)