$3\mathrm{.}18$ Consider a steady$-$state conduction problem governed by Laplace's equation with convective

boundary conditions $($see Fig. P$3\mathrm{.}2).$ The formal statement of the boundary condition is

$-$kdel$\frac{T}{d}$ely, which can be readily cast into finite$-$difference form as

$\frac{\text{:}{T}_{}}{}y.$ Use the control$-$volume approach to develop an expression for the

boundary condition at point $0.$ Evaluate the T$.$E$.$ in this expression assuming that Laplace's equation

applies at the boundary point.