A 100 Kg Mass Is Blown Apart into a 90

A 100 kg mass is blown apart into a 90.0 kg piece and a 10.0 kg piece.After the blast,the two masses are moving apart with a relative velocity of 100 m/s.The velocity of the 10.0 kg mass after the explosion is 90.0 m/s.The total kinetic energy of the two masses after the explosion is

A) 63,200 J.
B) 45,000 J.
C) 30,400 J.
D) 23,400 J.
E) 4,500 J.