4) (20 pts.) (Section 6.3 in book) The number of earthquakes occurring in a year is approximately normally distributed with mean 20.8 and standard deviation 4.5

a) What z-score corresponds with 14 earthquakes?

b) What is the probability that in a given year there will be less than 14 earthquakes?

c) What is the probability there will be more than 21 earthquakes?

d) What is the probability that there will be between 14 and 21 earthquakes in a given year?