Question $6.$ Bonus. $(20$ pt$)$

Heat exchanger design.

You are assigned to build a heat sink with a fin design for a circuit board. A circuit board houses electronic components generating the heat with a temperature of $T_b=60C.$ The heat generated by the board is released into the air at a temperature of $T_{}=20C$ with $h=50(\frac{W}{m^2}*(K)).$ An aluminum fin is added to help the heat release. The fin has a fin area of $A_{\text{f}\text{i}\text{n}}=0\mathrm{.}15(m^2)$ and an unfinned area of $A_{uf}=0\mathrm{.}01m^2.$ The fin efficiency is ${}_{\text{f}\text{i}\text{n}}=0\mathrm{.}975.$

Question:

Determining the heat transfer rate $(q(W))$ of the fin.