The annual precipitation in inches per year in Tucson, Arizona, for the
past thirty years are as follows: 11.37, 10.55, 8.68, 9.62, 6.93, 14.80, 10.64,
14.76, 15.19, 14.56, 9.68, 11.13, 11.60, 7.19, 12.69, 11.86, 14.81, 8.07, 11.15,
8.00, 9.55, 11.02, 19.54, 8.63, 12.33,8.53, 16.55, 19.74, 18.40, and 4.35.
Assume the annual precipitation follows a Poisson process.
(a) On average, how often will the annual precipitation exceed 11 in./yr?