3. A handle structure is made from ASTM grade 35 cast iron (please refer to Table A-24). It is subjected to F = 800 N, as shown. We need to analyze the state of stress and safety in rod AB. It is suggested that point A (located on top surface of the shaft, along the y axis, as shown in the figure) is a critical point in the structure. Determine (a) the principal and max shear stresses at point A. (b) the factors of safety at critical point A based on Coulomb Mohr, and modified Mohr theories 10 mm radius 100 mm 25 mm B 180 mm 6 mm radius