4.28 The velocity of water flow in the nozzle shown is given by the following expression: V = 2t/(1 - 0.5x/L)², where V = velocity in feet per second, t = time in seconds, x = distance along the nozzle, and L = length of nozzle = 4 ft. When x = 0.5L and t = 3 s, what is the local acceleration along the centerline? What is the convective acceleration? Assume that quasi-one-dimensional flow prevails.