8. In a tensile test on mild steel, the gauge length was 800 mm and diameter 25 mm. The load at the proportional limit was 50 kN and the yield

force is 76 kN. The extension on 800 mm gauge length was 0.058 mm under a load of 25 kN. Calculate the (a) stress at proportional limit (b) Yield stress and (c) Modulus of elasticity (Gauge length = Initial length, Extension = change in length)