A motorcyclist sees that the traffic lights are red 40m ahead of her. She is traveling at a velocity of 20ms^-1 and comes to rest at the lights. Find the deceleration she experiences, assuming it’s constant.

The basketball coach tells his team to run sprints back and forth across the court, which is 30 m long. they start at the left end of the court, run back and forth 6 times, then end back at the left end of the court where they began. what distance did they run? what is their displacement?