Of the following, which change in motion took the greatest amount of time? a) a ball falling at 73 m/s and hitting the ground at 9.8 m/s2. b) an object speeding up from 64 m/s to 129 m/s at an acceleration of 9.8 m/s2. c) a horse slowing from a 90 m/s velocity to a 38 m/s velocity at an acceleration of 8.2 m/s2. d) a car slowing down at an acceleration of 5.6 m/s2 from a speed of 45 m/s to a speed of 9 m/s.