\text { A uniform beam } AB \text { of weight } 100 ~N \text { and } 6 ~m \text { long had two bodies of weights } 60 ~N \text { and } 80 ~N \text { suspended } \text { from its two ends } A \text { and } B \text {, respectively. } A \text { t what distance from } B \text {, the beam should be supported so that it } \text { may rest horizontally? }