a) Calculate and plot the air specific impulse pair =T/(9) and specific fuel consumption SFC=9/T as a function of the stagnation pressure ratio for an ideal turbojet engine. Assume the flight Mach number to be 2.7, with 7 = 1.4, T = 400 R, QR = 19000 BTU/lbm, c = 0.24 BTU/Ibm R, and 6.8. Plot the results over the range from = 1.0 to the point at which the thrust goes to zero. (Feel free to use a spreadsheet or plotting program.) b) Obtain an analytic expression for the compressor ratio, that just leads to zero thrust. Write in terms of y, Mo, and T. Check that the value calculated using the data of part (a) agrees with the graphical result of part (a).