62 MPa, 9.8 An extruded beam has the cross section shown and a uni- form wall thickness of 5 mm. Knowing that a given vertical shear force V causes a maximum shearing stress r = determine the shearing stress at the four points indicated. [7.75, 3.41, 27.9, 58.0 MPa] 15 mm 15 mm 15 mm H H 15 mm 15 mm 40 mm 40 mm