The jet engine on a test stand in Fig. P3.50 admits air at20C and I atm at section i, where A, = 0.5 m and V, =250 m/s. The fuel-to-air

ratio is 1:30. The air leaves section 2at atmosphere pressure and higher temperature, where V = 900 m/s and A, 0.4 m. Compute the horizontal test stand reaction R, needed to hold this engine fixed.