An elastic spring of stiff ness 0.4 kN m 1 is suspended vertically with a load attached to its lower end. When displaced, the load is seen to oscillate with a periodic time of 1.27 s. Determine (a) the magnitude of the load, (b) the acceleration of the load when it is 25 mm from the equilibrium position and (c) the tension in the spring when the load is 25 mm from the equilibrium position.