4 (25p): Answer the following questions. a) The flow velocity measurements are given in the figure. What is the maximum roughness height (k) that will provide the conditions for the hydraulic smooth regime? To solve the problem, select one of the equations given below. u u. = 5.5+5.75 log yu V u U. = 8.5+5.75 log E ri v=1.5x10 m/s u-5.8 ms Plane surface b) Water flows with a discharge of 18 lt/s in a pipe which has 15 cm diameter and 2 mm roughness height (k). In this condition head loss occurs 3 cm for 1 m length. Determine the flow type and regime in accordance with the boundary conditions (-1.3x10 Ns/m. p-1000 kg/m).