A large spacecraft has a mass of 125,000 kg. Its orbital-maneuvering engines produce a thrust of 50 kN. The orbiter is in a 400-km circular earth orbit. A delta-v maneuver transfers the spacecraft to a coplanar 300 km by 400 km elliptical orbit. Neglecting propellant loss and using elementary physics (linear impulse equals change in linear momentum, distance equals speed times time):A. Estimate the time required for the Av burn. B. Estimate the distance traveled by the spacecraft during the burn. C. Calculate the ratio of your answer for (b) to the circumference of the initial circular orbit. D. What percent of the initial mass was expelled as combustion products?