An airline claims that there is a 0.10 probability that a coach-class ticket holder who flies frequently will be upgraded to first class on any flight. This outcome is independent from flight to flight. Sam is a frequent flier who always purchases coach-class tickets. Requried:
a. What is the probability he will receive at least one upgrade during the next two weeks?
b. What is the probability that in a set of 20 flights, Sam will be upgraded 3 times or fewer?