A converging-diverging nozzle operates at steady state. Air as an ideal gas with k 5 1.4 flows through the nozzle, discharging to the atmosphere at 14.7 lbf/in.2 and 5108R. A normal shock stands at the exit plane with px 5 9.714 lbf/in.2 The exit plane area is 2 in.2 Upstream of the shock, the flow is isentropic. Determine
(a) the throat area, in in.2
(b) the entropy produced in the nozzle, in Btu/8R per lb of air flowing.