A de Laval nozzle with an exit area ratio of 1.688 exhausts air from a large reservoir into ambient conditions at p = 100 kPa. 

a. Show that the reservoir pressure must be 782.5 kPa to achieve ideally expanded exit conditions at M = 2. 

b. What are the static temperature and pressure at the throat if the reservoir temperature is 17°C with the pressure as in (a)? 

c. If the reservoir pressure were lowered to 700 kPa, what would be the exit condition (overexpanded, ideally expanded, under expanded, subsonic flow in entire nozzle)?  

d. What reservoir pressure would cause a normal shock to form at the exit?