The figure below shows the cross section of a beam, with each square measuring \( 10 \mathrm{~mm} \times 10 \) mm . If the largest internal shear force in the beam is 200 kN , what is the value of the largest shear stress and where does it occur? The figure below shows the cross section of a beam, with each square measuring \( 10 \mathrm{~mm} \times 10 \) mm . If the largest internal shear force in the beam is 200 kN , what is the value of the largest shear stress and where does it occur?