A relation is a function if you associate exactly one output for every input. This means that, when you choose a value for x, there must be only one correspondent value for y. This only happens in the top-right parabola.
It would be .546% increase per year. You divide 292662.70 by 268000 and get 1.092025 and then divide by 2 for the years and get .546. Hope this helps
Luke: 1 practice 1 lap, 2 practices 2 laps, 3 practices 3 laps, 4 practices 4 laps
Alex: 1 practice 3 laps, 2 practices 6 laps, 3 practices 9 laps, 4 practices 12 laps
Luke ran 3 laps for 3 practices, and Alex ran 9 laps for 3 practices.
