4. Consider steady laminar flow of a Newtonian liquid down an inclined plane and show that the velocity profile for a fully developed, incompressible flow is given by Ux=gL2sin[Ly21(Ly)2] a) Obtain an expression for the film thickness L, as a function of volumetric flow rate per unit width. b) An oil has a viscosity of 0.8kg/m.sec and a density of 8102kg/m3. What should the mass flow rate of the film down a vertical wall be in order to have a film thickness of 2.5mm