Solve this Transport phenomena Question and don't copy from internet sources otherwise I will downvote your answer and correct solution needed here.

(b) A wetted wall column is used to measure mass transfer coefficients. A liquid of density and viscosity flows down inside a tube of radius R shown below. After an initial region, the flow becomes fully developed and the thickness of the liquid layer is constant at h. Simplify the Navier-Stokes and continuity equations to obtain Vz(r) under laminar conditions