A 140 kg stationary crate is pulled by a force of 390 N along a horizontal surface. a) The coefficient of static friction between crate and surface is s = 0.25. Is the applied force large enough to begin moving the crate? Use physics calculations to prove that it is. b) The coefficient of sliding friction between crate and surface is k = 0.17. Find the net force and the acceleration of the crate once it does move. c) If the acceleration occurs for 2.80 s, how far will the box move in this time?