A student researcher performed a chromatographic separation of caffeine and aspartame. The retention time for caffeine, tc, was found to be 207.9 s with a baseline peak width, wc, of 13.9 s and the retention time for aspartame, ta, was 264.2 s with a baseline peak width, wa, of 22.2 s. The retention time for the unretained solvent methanol was 47.0 s. Calculate the average plate height in micrometers for this separation, given that it was performed on a 16.8-cm long column.