6.18 For the beam and loading shown, determine the minimum required width b, knowing that for the grade of timber used, all = 12 MPa and Tall 825 kPa. Tall= 2.4 kN 4.8 kN 7.2 kN B CV D 150 mm A 1 m Fig. P6.18 1 m 1 m 0.5 m