The flatbed truck is traveling at the constant speed of 60 km/h up the 15-percent grade...

The flatbed truck is traveling at the constant speed of 60 km/h up the 15-percent grade when the 100- kg crate which it carries is given a shove which imparts to it an initial relative velocity ? = 3 m/s toward the rear of the truck. If the crate slides a distance x = 2 m measured on the truck bed before coming to rest on the bed, compute the coefficient of kinetic friction μ_k between the crate and the truck bed.