Consider $1$D steady$-$state heat transfer

a$.$ An insulation layer $($conductivity $k=0\mathrm{.}01\frac{W}{m}K,$ length $200$ mm $)$ is shown in Figure $5,$ where $T_0=20C$ and its right side loses heat by convection to the surrounding air of $T_{}=0C$ with heat transfer coefficient $h=5\frac{W}{m^2}K.$ Use $5$ nodes and the finite difference scheme to calculate the temperatures at node $1$ to node $4$

Figure $5.$ Insulation layer with nodes.

$4$