A 10.0-kg block is released from rest at point \textcircled{A} in the figure below. The track is frictionless except for the portion between points \textcircled{B} and \textcircled{C}, which has a length of 6.00 m. The block travels down the track, hits a spring of force constant 2 400 N/m, and compresses the spring 0.350 m from its equilibrium position before coming to rest momentarily. Determine the coefficient of kinetic friction between the block and the rough surface between points \textcircled{B} and \textcircled{C}.