The beam cross section below is symmetric in both y and z directions. The thicknesses in mm are indicated. 1 mm A +4 B C 3 mm 2 mm The shear flow at point A is 44 N/mm. The shear flow at point B is 55 N/mm. The shear flow at point C is 224 N/mm. Calculate the maximum shear stress at any of these three points. Give you answer in MPa (N/mm) to 1 decimal place, but without the units.