A recent study in NJ showed that 50% of all patients will return to the same dentist. Suppose nine patients are selected at random, what is the probability that: (a) exactly five of the patients will return? (b) All nine will return? (c) At least eight will return? (d) At least one will return? (e) How many patients would be expected to return to the same dentist, i.e., what is the mean of the distribution?