A four-engine commercial jumbo jet is cruising at a constant speed of 800 km/h in level fl...

A four-engine commercial jumbo jet is cruising at a constant speed of 800 km/h in level flight when all four engines are in operation. Each of the engines is capable of discharging combustion gases with a velocity of 775 m/s relative to the plane. If during a test two of the engines, one on each side of the plane, are shut off, determine the new cruising speed of the jet. Assume that air resistance (drag) is proportional to the square of the speed, that is, FD = cv2, where c is a constant to be determined. Neglect the loss of mass due to fuel consumption.