Usually, Tony travels to Bunbury from Perth city in 2.50 hours. One day he increases his average speed by 12.0 km/h and takes 22.5 minutes less time to reach Bunbury. (a) What was his usual average speed? What was the distance travelled? (b) On the way he stopped at a rail crossing (6.00 m wide) and a train (total length 144m) decelerating at -0.585 ms-2 just entered the crossing with a velocity of 13.7 m s-1. Sketch a diagram and find the minimum time for the last carriage of the train to clear the crossing.