c) A thick cylinder has an internal diameter of 75 mm and external diameter of 125 mm. Ends are closed and it comes an internal pressure of 60 MN/m2. Neglecting end effects, calculate the hoop stress and radial stress at radii of 37.5 mm, 40 mm, 50 mm, 60 mm and 62.5 mm. Plot the values on a diagram to show the variation of these stresses through the cylinder wall. What is the value of the longitudinal stress in the cylinder? [ 20 Marks]