The drag coefficient of an aircraft can be expressed as: CD = 0.020 + 0.125CZ. It flies at an altitude of 9,000m at a speed of M = 0.85. It has a weight of 111kN and a wing area of 35m. a) In straight and level flight at M = 0.85, find the coefficients of lift and drag. b) Find the thrust required in kN. c) If Cmax = 1.75, find the stall speed as an equivalent airspeed and a true airspeed in knots at 9,000m.