2. This beam has a "double-T" cross section. Three plates are joined together to form a composite cross section. Determine the shear stress on the stem-to-flange junctions if the (vertical) shear force acting on the cross section is 100 kN. What shear flow must one of the stem-to-flange junctions resist when this 100 kN shear force is acting? 50 mm 75 mm 50 mm 20 mm 20 mm. 20 mm 150 mm