1. The problem statement, all variables and given/known data A toboggan carrying two children with a total mass of 85.0 kg reaches its maximum speed at the bottom of a hill, and then glides to a stop in 21.0 m along a horizontal surface. The coefficient of kinetic friction between the toboggan and the snow surface is 0.110. Calculate the work done by the kinetic friction? 2. Relevant equations W=FCosθΔd 3. The attempt at a solution m = 85 kg Δd = 21.0 m θ = 0 W = ? Mu = 0.110 I'm pretty confused on this, do I somehow get Mu to Ff and then plug it in to the work equation? The final answer is -1.90 x10^3 J but from what I've tried I never got it.