(b) The fixed-pinned cantilever beam AB illustrated in Figure 4, lying on the x-z plane, has a length of 6m and is made from a weightless circular cross-section with radius of 250 mm. It has two same material levers attached, one 2.5 m and another 1.25 m long, (parallel to the y axis), carrying each uniform distributed load w (creating torsion on AB). If the stress that causes the breakdown of the section is 400N/mm determine the maximum value of w according to the von Mises and Tresca theories. [19 marks] 301 3m C w kN/m w kN/m 2.5m 1.25m B Figure 4