1. The problem statement, all variables and given/known data Leroy, who has a mass of 100kg, is skateboarding at 9.0 m/s when he smacks into a brick wall and comes to a dead stop in .2s a. Show that his deceleration is 45 m/s^2. b. Show that the force of impact is 4500N. 2. Relevant equations I think the only equations that are needed are these: a= NetForce/m Weight = mg Force= ma 3. The attempt at a solution I tried a number of things, but I couldn't figure out how to get the deceleration. It's not in my book anywhere. All I have are the equations for acceleration. I've tried various configurations, but nothing seems to make sense.