The driver is moving at a velocity of 30 m/s then stops (final velocity of 0 m/s) in 5 seconds. What deceleration is required?

Kaleb has decided to forget about flying and buys a boat instead.  If his boat increases its speed from 5.0 m/s to 7.5 m/s over a distance of 50.0 m.  What is the boat's acceleration? (please hand-write it and make it clear)

Joe decides to race his younger sister, Debbie, and gives her a 25 m head start. At the instant Joe starts running, his sister reaches a velocity of 12 m/s [W] while accelerating at 0.4 m/s2 [W]. If Joe accelerates at a rate of 1.2 m/s2 [W], how long does it take for him to catch up to his sister?