A pin-jointed truss ABC shown below consists of two links AB and BC. These links are 6 mm thick and 20 mm wide as shown. There are support brackets at A and C. All pins are 12 mm in diameter and a vertical force, P = 7 kN is applied at pin B as shown. The angle 0 =40 deg. and the angle = 0 + 20 deg. The normal stress in link AB is (The result is accurate to one decimal place, in the unit MPa. Please write down only the value of your final result) - 12mm B 20mm -1.0m. + P B