Cx The two-bar truss ABC has pin supports at points A and C, which are 2.0 m apart. Members AB and BC are steel bars, pin connected at joint B. The length of bar BC is 3.0 m. A sign weighing 5.4kN is suspended from bar BC at points D and E, which are located 0.8 m and 0.4 m, respectively, from the ends of the bar. Determine the required cross-sectional area of bar AB if the allowable stresses in tension and shear are 125 MPa and 45 MPa, respectively. Disregard the weights of members AB and BC. A =? The 45MPA = P A 3 125 MP 2.0 m 0.8 m +-0.9m+0.9m 0.4 m W-54 kN F:0; Ay +C-R₂ = C ΣF:0, By+ Ay + Cy - 5.4KN=C 770 EM:0; - Cy (3m) - Ay (34)-Ayland+ 64(1 5