An Olympic archer is able to hit the bull's-eye 84% of the time. Assume each shot is independent of the others. If she shoots 6 arrows:
a.) What is the probability that her first bull's-eye come on the fifth arrow?
b.) What is the probability that she gets exactly 4 bull's-eyes?
c.)How many bull's-eyes do you expect her to get out of the 6 arrows and what is the standard deviation?
d.) Now suppose the archer shoots arrows until she hits her first bull's-eye. How many arrows do you expect her to shoot?