A block attached to a horizotal spring oscillates on a frictionless surface, the x-t graph of the block is shown below. At t = 1.5 s, which of the following is maximum? (at 1.5 seconds, the graph is is touching the x axis, the oscilations is at equilibrium).. Select all apply. mass-spring speed the magnitude of the acceleration the magnitude of the spring force kinetic energy of the block spring potential energy of the spring none of the above