Two masses, each weighing 1.0 × 103 kilograms and moving with the same speed of 12.5 meters/second, are approaching each other. they have a head-on collision and bounce off away from each other. assuming this is a perfectly elastic collision, what will be the approximate kinetic energy of the system after the collision?
a. 1.6 × 105 joules
b. 2.5 × 105 joules
c. 1.2 × 103 joules
d. 2.5 × 103 joules