4. A formula to estimate the volume rate of flow, Q, flowing over a dam of length, B,is given by the equation Q=3.09 B H^{3 / 2} where H is the depth of water above the top of dam (called the head). This formula gives Q in ft/s when B and H are in feet. Is the constant, 3.09, dimensionless? Would this equation be valid if metric units were used? [11 points]

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