Afluid has a dynamic viscosity of 0.048 pa. s and a specific gravity of 0.913. for the flow of such a fluid over a flat solid surface, the velocity at a point 75 mm away from the surface is 1.125 m/s. calculate the shear stress at a point 50 mm away from the solid surface if the velocity distribution of the fluid can be represented by a parabolic velocity profile with the vertex of the parabola at a point 75 mm away from the surface where the velocity is 1.125 m/s? the general equation of parabola can be assume to be: v = a + by + cy2 , where a, b, and c are constants.