A square plate of edge length 12.0 cm and negligible thickness has a total charge of 5.80 x 10^-6 C. Estimate the magnitude E of the electric field just off the center of the plate (at, say, a distance of 0.50 mm from the center) by assuming that the charge is spread uniformly over the two faces of the plate. b) Estimate E at a distance of 49 m (large relative to the plate size) by assuming that the plate is a point charge. Five stars for most thorough explanation.