Two people stand facing each other at a roller skating rink then push off each other. a). What is the momentum of the system before they push off each other? b. What must be the momentum of the system after they push off each other? c. If the girl skater has a mass of 54 kg and moves backward at 5 m/s, what is the velocity of the boy skater if his mass is 62 kg? (Round answer to nearest tenth). d. If the force applied between the two skaters occurs over 1.5 seconds, what is the force exerted on each of the skaters?