A rocket is moving away from the solar system at a speed of 7.5 ✕ 103 m/s. It fires its engine, which ejects exhaust with a speed of 5.0 ✕ 103 m/s relative to the rocket. The mass of the rocket at this time is 6.5 ✕ 104 kg, and its acceleration is 4.0 m/s2.
What is the velocity of the exhaust relative to the solar system? (B) At what rate was the exhaust ejected during the firing?