Solve the following wave equation to find the displacements for a spring stretched between x = 0 and x = 80, spring is fixed at this both ends. At the beginning you can assume velocity is zero and displacements are defined as: x < 20 u = 0.03 x x>20 u = 0.6-0.03 (x-20) at = 3.136x10 au x Solve the wave equation with centered finite differences in order to find displacements and also you should specify the period of the oscillation by using your results.