During an experiment a student records the net horizontal force exerted on an object moving in a straight line along a horizontal frictionless track. The graph above shows the force as a function of time. Of the following, which is the best approximation of the magnitude of the change in momentum of the object between 0 s and 4 s? (A) 20 kg•m/s (B) 30 kg•m/s (C) 40 kg•m/s () The magnitude of the change in momentum​