After flowing over the spillway of a dam, 250 m3/s of water passes over a rectangular level apron (So = 0; n = 0.025). The velocity of water at the bottom of the spillway was measured to be 12.8 m/s. The width of the apron is 50 m and the depth of flow just after the apron is 3 m. Conditions are such that a hydraulic jump would occur. Find the length of the apron if the jump is to be contained within it. Determine also the energy lost in the entire length of apron.