U(x) = 12a D (x) (Hint. This seems like a complicated problem, but it's actually a super simple application of the Conservation of Mass! However, the information it provides is very useful and is still used today in designing wind farms. When solving the problem, one important feature you must notice is that the control volume diameter at the inlet and outlet are the same.) Upo Uo 40 uo D(x) Control volume Turbine rotor U(x) x (b)