NORMAL 0.8> DISTRIBUTION LOGNORMAL | DISTRIBUTION a / 0.2- 4.2 ffKe 4 68 MODE MEAN MEDIAN NORMAL LOGNORMAL MODE: U exp (u- o7) MEDIAN: Ul exp (x) MEAN: Ll exp (ut+ 2 02) FIGURE 5. Frequency Curves of Normal and Lognormal Distributions for u = 0 and of = 0.5. 253