If a velocity distribution over a plate is given by u(y) = (2/3) y-y² in which u is the velocity (m/s) at a distance y meter above the plate, determine the shear stress at y=0 and y=0.15 m. Also sketch the velocity profile and shear stress profile from y=0 to y=0.15 m. Take dynamic viscosity of fluid as 8.63 poises.