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1. The graph shows the velocity v(t), of a particle moving along the x-axis for 0 S t - 9. a. At what time(s) is the speed of the particle greatest? 2- b. When does the particle reverse direction? 4 -1 6 7 8 9 -2- c. What time interval(s) is the particle speeding up? d. What time interval(s) is the particle moving left? e. At which of the times, t = 1, t = 3,t = 5 ort = 6.5 , is the acceleration of the particle greatest? Justify