A Rocket Exhausts Fuel with a Velocity of 1500 M/s

Multiple Choice

A rocket exhausts fuel with a velocity of 1500 m/s, relative to the rocket.It starts from rest in outer space with fuel comprising 80 per cent of the total mass.When all the fuel has been exhausted its speed is:

A) 3600 m/s
B) 2400 m/s
C) 1200 m/s
D) 880 m/s
E) 400 m/s