Chapter 32, Problem 12P

To determine

To graph: The electric potential of the unit square as a contour plot by solving the Poisson equation that defines the electric potential over the square, considering zero voltage at the boundaries, the value of point charge source as ${\rho }_v/\epsilon \left(0.7,0.7\right)=1$ and ${\rho }_v/\epsilon \left(0.3,0.3\right)=-1$, and the step size of $0.1$ along the horizontal and vertical dimensions.