A small spherical heating core is encased in a thick, uniform insulating shell. Heat conducts radially outward through the insulating material at a steady rate. Let \(\left|\dfrac{\Delta T}{\Delta x}\right|_1\) and \(\left|\dfrac{\Delta T}{\Delta x}\right|_2\) represent the magnitude of the local temperature gradient at concentric radial distances \(r_1 = R\) and \(r_2 = 2R\), respectively. Which of the following correctly compares the magnitude of the temperature gradient at \(r_2\) to that at \(r_1\)?