The number of pizzas consumed per month by university students is normally distributed with a mean of 7 and a standard deviation of 4.

A. What is the probability that in a random sample of size 9, a total of more than 81 pizzas are consumed?

The length, X, of a fish from a particular mountain lake in Idaho is normally distributed with mean = 9.2 inches and standard deviation = 1.3 inches

a) Write the event "a fish chosen has a length of over 7.2 inches" in terms of X:

b) Find the probability of this event: