A tour operator has a bus that can accommodate 20 tourists. The operator knows that tourists may not show up, so he sells 23 tickets. The probability that an individual tourist will show up is 92.5%, independent of all other tourists.

a) (4 pts) Explain why this is a binomial experiment. (You need to check each of the 4 properties of Binomial Experiment. Do not just list the properties).

b) (4 pts) Find the probability that the number of people who show up will exceed the capacity of the bus.