A jet propelled engine having two jets and working on turbojet system has a velocity of 200 m/s, when flying an altitude of 12000 m, the density of air at this altitude being 0.1725 kg/m³. The resistance or drag of the plane is 650kg, and the propulsion, η of the jets is 50%, Given that the overall efficiency of the turbulant is 18%, and the calorific value of the fuel used is 11750 kcal/kg, estimate (i) absolute velocity of the jet (ii) volume of air compressed/min (iii) diameter of the jet (iv) Power output of the unit (v) fuel consumption/thrust hp-hr and (vi) air-fuel ratio of the unit at the given altitude.