Mary and Sally are in a foot race (see the figure). When Mary is 22 m m from the finish line, she has a speed of 4.0 m/s m / s and is 5.0 m m behind Sally, who has a speed of 5.0 m/s m / s . Sally thinks she has an easy win and so, during the remaining portion of the race, decelerates at a constant rate of 0.32 m/s2 m / s 2 to the finish line. (Figure 1) Figure1 of 1 What constant acceleration does Mary now need during the remaining portion of the race, if she wishes to cross the finish line side-by-side with Sally?