A pair of infinite parallel planes are separated by a distance d, with one above the other. The top plane has a uniform charge density σ. The bottom plane has a uniform charge density −σ. a. Determine the electric field everywhere. [Note that there is no slab between the planes for part a.] b. An infinite conducting slab is placed between the two planes with top and bottom faces parallel to the two planes and without touching the two planes. Determine the induced charge densities on the top and bottom of the conducting slab.