shows a surfer running to the right on a surfboard. Assume that both the surfer and the surfboard are ini- tially moving to the right with a speed 59f t/s. Model the surfer as a particle located at the open circle, which is the surfer's mass center. The surfer has a weight of 180lbs. Ignore the horizontal force that the water applies to the surf- board and assume that surfboard does not rotate. The surfboard has a weight of 2lbs. Find the speed of the surfboard in the hor- izontal direction if the surfer starts run- ning to the right with a speed 3f t/s