The sleigh lands on a snowy and icy patch (i.e. a frictionless surface) with a known initial speed U, as illustrated. The parachute exerts the equivalent of an unknown applied force A on the sleigh at an angle 0 above the incline, causing the sleigh to come to rest after sliding a known distance D down the incline. Assuming the sleigh remains on the incline, use the work-energy theorem to determine the unknown applied force A.