1.1 Two solid cylindrical rods AB and BC are welded together at B and loaded as shown. Knowing that the average normal stress must not exceed 175 MPa in rod AB and 150 MPa in rod BC, determine the smallest allowable values of d₁ and d₂. 1.2 Two solid cylindrical rods AB and BC are welded together at B and loaded as shown. Knowing that d₁ = 50 mm and d₂ = 30 mm, find the average normal stress at the midsection of (a) rod AB, (b) rod BC. 1.3 Two solid cylindrical rods AB and BC are welded together at B and loaded as shown. Determine the magnitude of the force P for which the tensile stress in rod AB has the same magnitude as the compressive stress in rod BC. 300 mm 250 mm 3 in. 2 in. 30 kips B Fig. P1.3 30 in. 30 kips 40 in. RO -di 40 kN -d₂ 30 kN Fig. P1.1 and P1.2