I'm struggling on a presentation problem in my physics class. The problem reads: A crate containing machine parts sits unrestrained on the back of a flatbed truck traveling along a straight road at a speed of 80 km/h. The driver applies a constant braking force and comes to stop in a distance of 22 m. What is the minimum coefficient of friction between the crate and the truck bed if the crate is not to slide forward? Ok since the crate doesn't slide forward I'm thinking this would be static friction correct?? Other than that I'm clueless, I don't necessarily want the problem solved for me, just some formulas, ideas, or just how to setup this problem up. Thanks a lot everyone!!