After accelerating with a constant acceleration of -2.50 m/s^2 for 2.50 s in a displacement of 50 m, a 3000-kg truck hits a tree. a)Find the velocities (in mph) of this truck when it started decelerating and with which it hits the tree.

b)Find the acceleration and time for this truck, after the same displacement, to hit the tree with a velocity of 20 m/s.

c)Find the acceleration and time for this truck, after the same displacement, to come to rest at the tree.