A dart of mass \(m = 0.05\text{ kg}\) is launched horizontally toward a wooden block of mass \(M = 0.45\text{ kg}\) that is initially at rest on a rough horizontal floor. The dart embeds itself into the block over a negligible time interval. After the collision, the dart-block system slides a distance \(d = 1.0\text{ m}\) along the surface before coming to rest. The coefficient of kinetic friction between the block and the floor is \(\mu_k = 0.20\). Assuming the acceleration due to gravity is \(g = 10\text{ m/s}^2\), what was the initial launch speed of the dart?