A meteor whose mass was about 1.0 X 108 kg struck the Earth (mE = 6.0 x

Question:

A meteor whose mass was about 1.0 X 108 kg struck the Earth (mE = 6.0 x 1024 kg) with a speed of about 15 km/s and came to rest in the Earth.
(a) What was the Earth’s recoil speed?
(b) What fraction of the meteor’s kinetic energy was transformed to kinetic energy of the Earth?
(c) By how much did the Earth’s kinetic energy change as a result of this collision?