A transportation company loads crates with the help of spring system as shown in the figure below. The crate is placed in a holder H in front of the spring and an electric motor compresses the spring by pushing H to the left. When the spring is released, the crate is accelerated towards a ramp ABC. When the spring is fully decompressed, the crate loses contact with the spring at A. The mass of the crate is 45 kg. spring crate C O O HA B 1.2m Zoom image Assume that the surface of the ramp is frictionless and that the masses of the spring and the holder are negligible compared to the mass of the crate. a) The block arrives at C with a speed of 0.90 m s-1. Show that the elastic energy stored in the spring is 547 J. 13T] b) Calculate the speed of the block at A. [ /2A] c) The spring decompression takes 0.42 s. Determine the average force that the spring exerts on the block. [ /2K]