Sociology: Ethics

 The one-time fling! Have you ever purchased an article of clothing (dress, sports jacket, etc.), worn the item once to a party, and then returned the purchase? This is called a one-time fling. About 10% of all adults deliberately do a one-time fling and feel no guilt about it. In a group of seven adult friends, what is the probability that

(a) no one has done a one-time fling?

(b) at least one person has done a one-time fling?

(c) no more than two people have done a one-time fling?