The uniform bar AB weighs 100 lb. If both springs DE and BC are unstretched when θ = 90°,...

The uniform bar AB weighs 100 lb. If both springs DE and BC are unstretched when θ = 90°, determine the angle θ for equilibrium using the principle of potential energy. Investigate the stability at the equilibrium position. Both springs always act in the horizontal position because of the roller guides at C and E.