The fastest man on the planet, Usain Bolt, ran a 400m race with times of 9.68s, 9.72s, 9.74s, and 9.70s for each quarter of the race. a) Find his average speed during each quarter segment of
the race. b) Assuming that Usain's instantaneous speed at the finish line was the same as the
average speed during the final quarter segment, find his average acceleration for the entire race.