A copper rod is 0.871 m long with a rectangular cross section of dimensions 0.0533 m by 0.0775 m . The ends of the rod are held at 58.3 ∘ C and 97.7 ∘ C , but the rod is otherwise insulated from its environment. Find the heat current (the amount of heat that flows per unit time) through the rod. The thermal conductivity of copper is 385 W / (m ⋅ K) .