Remember the Four-Step plan:

1. Equilibrium: Draw an FBD of joint K, and write down the two equilibrium equations from this FBD.
2. Force/elongation equations: Write down the force/elongation equation for each member:  e_i = F_iL_i/E_iA.
3. Compatibility equations:  Write down the elongation/displacement compatibility equation for each member: e_i = u_K cosθ_i + v_K sinθ_i. Take care in defining the member angles θ_i.
4. Solve: Solve the equations generated in Steps 1-3 for the three axial loads in the three members.

You are asked to provide your answers in the appropriate parts a)-g) as asked in the problem statement.

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