If the tapering of the tube is not too severe, then the flow is nearly Poiseuille and can be described by Q=((-pi*R^4)/8mu)*dp/dx. Using this expression as well as dR=(R^2/(E*h))dp, derive an expression for R in terms of the inlet radius R0, mu, the flow rate Q, E, tube thickness h, and the axial position within the tube, x.