In the figure, the inner (shaded) region $A$ represents a sphere of radius $\mathrm{r}_{\mathrm{A}}=1$, within which the electrostatic charge density varies with the radial distance $r$ from the center as $\rho_A=k d$, where $k$ is positive. In the spherical shell $B$ of outer radius $r^{\mathrm{r} B}$, the electrostatic charge density varies as $\rho_B=\frac{2 k}{r}$. Assume that dimensions are taken care of. All physical quantities are in their SI units.