79. Let X
the hourly median power (in decibels) of received radio signals transmitted between two cities. The authors of the article “Families of Distributions for Hourly Median Power and Instantaneous Power of Received Radio Signals”

(J. Research National Bureau of Standards, vol. 67D, 1963:

753–762) argue that the lognormal distribution provides a reasonable probability model for X. If the parameter values are
3.5 and
1.2, calculate the following:

a. The mean value and standard deviation of received power.

b. The probability that received power is between 50 and 250 dB.

c. The probability that X is less than its mean value. Why is this probability not .5?