An athlete is training on a 100 m long linear track. His motion is described by the graph of his position vs. time, below. x (m) 100 80 D B 60 C 40 VA 20 t (s) 10 20 30 40 50 60 (a) For each segment of the graph, find the magnitude and direction of the athlete's velocity. magnitude VA m/s direction VA -Select--- magnitude VB m/s direction VB -Select--- magnitude Vc m/s direction Vc -Select--- magnitude VD m/s direction VD ---Select--- (b) What are the magnitude and direction of the athlete's average velocity over the entire 60 s interval? magnitude m/s direction -Select