Determine which of the given procedures describe a binomial distribution :

a. The number of tattoos in a group of 30 randomly selected college students.

b. The number out of the next ten customers at a hotdog stand order who order onions, assuming that each has the same probability of ordering onions.

c. The number of customers surveyed, while leaving a grocery store, until a customer responds that he or she spent more than fifty dollars.

d. The ages of every 5th person entering a department store