A non-Newtonian fluid is modelled by the equation pai = K(du/dr) where n = 0.8 and du dr K = 0.05 N s08/m. It flows through a tube 6 mm bore diameter under the influence of a pressure drop of 6400 N/m per metre length. Obtain an expression for the velocity profile and evaluate the following. (i) The centre line velocity. (0.953 m/s) (ii) The mean velocity. (0.5 m/s)