A brave but inadequate rugby player is being pushed backward by an opposing player who is exerting a force of 880 N on him. The mass of the losing player plus equipment is 86 kg, and he is accelerating at 1.2 m/s2 backward. Randomized Variables f = 880 N m1 = 86 kg m2 = 104 kg a = 1.2 m/s2 Part (a) What is the magnitude of the force of friction, in newtons, between the losing player's feet and the grass as he slides backwards? F1 =