The Aluminum Electrical Conductor Handbook lists a dc resistance of \(0.01558 \mathrm{ohm}\) per \(1000 \mathrm{ft}\) at \(20^{\circ} \mathrm{C}\) and a \(60-\mathrm{Hz}\) resistance of \(0.0956 \mathrm{ohm}\) per mile at \(50^{\circ} \mathrm{C}\) for the all-aluminum Marigold conductor, which has 61 strands and whose size is \(1113 \mathrm{kcmil}\). Assuming an increase in resistance of \(2 \%\) for spiraling, calculate and verify the dc resistance. Then calculate the dc resistance at \(50^{\circ} \mathrm{C}\), and determine the percentage increase due to skin effect.