An astronomer at the Mount Palomar Observatory notes that, during the Geminid Meteor shower, an average of 50 meteors appears each hour, with a variance of 9 meteors squared. The Geminid meteor shower will occur next week.
a) If the astronomer watches the shower for 4 hours, what is the probability that at least 48 meteors per hour will appear?
b) If the astronomer watches for an additional hour, will this probability rise or fall? Why?