An aluminum tube of inner diameter \(D_{i}=1 \mathrm{~mm}\) and wall thickness \(0.1 \mathrm{~mm}\) is used to transport a warm biological fluid. The tube is coated with \(N=500\) alternating layers of aluminum and aluminum oxide (sapphire), each of which is \(60 \mathrm{~nm}\) thick. Determine the thermal resistance in the radial direction for a unit tube length for the wall of the aluminum tube, as well as for the nanocomposite tube coating. Assume the aluminum mean free path is \(\lambda_{\text {mfp,Al }}=35 \mathrm{~nm}\). Comment on the effectiveness of the nanocomposite coating as a thermal insulator.