A 5.42 kg dartboard is attached to the free end of a spring that is oriented horizontally. The other end of the spring is fixed to a wall. A student throws a dart of mass 0.0423 kg at the dartboard and it gets stuck in the dartboard. As a result, the spring gets compressed by a maximum distance of 5.20 cm. Given that the spring constant of the spring is k = 122 N/m, find the speed of the dart v_o which strikes the dartboard. [Assume that there is no friction involved.]