A uniform beam resting on two pivots has a length L = 6.00 m and weight M = 220 lbs. The pivot under the left end exerts a normal force n1 on the beam, and the second pivot, located a distance l = 4.00 m from the end exerts a normal force n2. A woman with a weight of 130 lbs steps onto the left end of the beam and begins walking to the right. How far can the woman walk before the beam tips?