A string with a mass m = 6.00 g and a length L = 5.00 m has one end attached to a wall; the other end is draped over a small, fixed pulley a distance d = 3.00 m from the wall and attached to a hanging object with a mass M = 2.00 kg as in the figure below. If the horizontal part of the string is plucked, what is the fundamental frequency of its vibration?