7.10 Figure 7.32 shows the cross section of a levee which is 650 m long and is underlain by a 2.5-m-thick permeable sand layer. It was observed that the quantity of water flowing through the sand layer into the collection ditch is 13.5 m³/hr. What is the hydraulic conductivity of the sand layer? Elv. 175 m 2.5 m Figure 7.32 210 m Impervious Sand Ditch Elv. 158 m