1. Let A and B be independent events with Pr (A) = .3 and Pr (B) = .4. What is the probability that exactly one of the events A or B occurs?
2. Each box of a certain brand of candy contains either a toy airplane or a toy boat. If one-third of the boxes contain an airplane and two-thirds contain a boat, what is the probability that a person who buys two boxes of candy will receive both an airplane and a boat?