Please answer a,b,c.

A Newtonian fluid (density , viscosity ) flows laminarly in a tube with diameter D and length L. The pipe is inclined at an angle with the horizontal surface. The direction of fluid flow is from bottom to top. By ignoring the end effects, a. Set up and develop a shell momentum balance, so that an equation is obtained that states: b. Liquid velocity profile in a pipe, and c. Shear force on the inner wall of the pipe