Three solid cylindrical rods are welded together to form the compound axial member shown in the figure. The compound axial member is attached to a fixed support at A. Each rod has an elastic modulus of E = 47 GPa. Use the following values for the rod lengths and areas: L₁ = 1350 mm, L₂ = 1760 mm, L3 = 1300 mm, A₁ = 260 mm². A₂ = 155 mm², and A3 = 80 mm². What magnitude of external load P is needed to displace end D a distance of up = 30 mm to the right? Part 1 8₁ F₁ = Part 2 8₂ F₂ A = L₁ (1) mm/kN B L2 Find the relationship between 8₁, the elongation of rod (1), and the internal tensile force, F₁, in rod (1). Assume & is a positive value in units of mm and F, is a positive value in units of kN. So, the answer you enter for the ratio (8₁/F₁) must be in units of (mm/kN). mm/kN (2) C L₂ (3) Similar to the previous step, find the relationship between 2, the elongation of rod (2), and the internal tensile force, F2, in rod (2). Assume 2 is a positive value in units of mm and F2 is a positive value in units of kN. So, the answer you enter for the ratio (82/F₂) must be in units of ( mm/kN). D