Write a computer program to solve Exercise 3-102, allowing for an arbitrary mesh size. Also attempt to calculate the heat flow out the edge at $0^{\circ} \mathrm{C}$ if the plate is 3 $\mathrm{mm}$ thick and has a thermal conductivity of $200 \mathrm{~W} / \mathrm{m} \mathrm{K}$. Explore the effect of mesh size on the calculated heat flow by obtaining results for mesh sizes of $1 \mathrm{~cm}$, $0.5 \mathrm{~cm}, 0.2 \mathrm{~cm}$, and $0.1 \mathrm{~cm}$ : explain the anomalous behavior obtained.