Displacement need help?

Swimmers going down a waterslide 30m long push themselves off with an initial speed between 1m/s and 2m/s. They accelerate down with constant acceleration 0.8m/s² for the first 20m before more water is added and the acceleration is 1m/s² for the last 10m of the slide. For safety there must be at least 5s between... show more Swimmers going down a waterslide 30m long push themselves off with an initial speed between 1m/s and 2m/s. They accelerate down with constant acceleration 0.8m/s² for the first 20m before more water is added and the acceleration is 1m/s² for the last 10m of the slide. For safety there must be at least 5s between swimmers arriving at the bottom of the slide. Find the minimum whole number of seconds between swimmers being allowed to start the slide
0