The light rod is pivoted at O and carries the 4.9- and 10.2-lb particles. If the rod is released from rest at θ = 56° and swings in the vertical plane, calculate (a) the velocity v of the 4.9-lb particle just before it hits the spring in the dashed position and (b) the maximum compression x of the spring. Assume that x is small so that the position of the rod when the spring is compressed is essentially horizontal.