12. A body moves with constant velocity of 5m/s for 10s and then speeds up with constant acceleration of 2m/s² for 5s and again speeds up with a constant acceleration of 4m/s² for 5s and finally comes to rest in the next 10s with a constant deceleration
a) Draw the graph of velocity-time graph for 30s
b) Calculate the deceleration of the body in the last 10s c) Find the total distance travelled by the body​