A dart of mass \(m\) is moving horizontally with speed \(v_0\) toward a block of mass \(M\) that is floating at rest on the surface of a pond. The dart strikes the block and becomes embedded in it, after which the dart-block system moves a distance \(d\) along the surface before coming to rest. The water exerts an average horizontal resistive force of magnitude \(F\) on the system. Which of the following is a correct expression for \(F\)?