Solve the all parts of following question:
Question: A square metal plate of edge length 12 cm and negligible thickness has a total charge of 7.2 x 10-6 C.
Part A: Estimate the magnitude E of the electric field just off the center of the plate (at, say, a distance of 0.39 mm from the center) by assuming that the charge is spread uniformly over the two faces of the plate.
Part B: Estimate Eat a distance of 34 m (large relative to the plate size) by assuming that the plate is a point charge.
Give your answers in N/C.
Any help I can get on this question is greatly appreciated! I'm not too familiar with this question.