A certain company sends 50% of its overnight mail parcels via express mail service E1. Of these parcels, 1% arrive after the guaranteed delivery time (denote the event late delivery by L). Suppose that 10% of the overnight parcels are sent via express mail service E2 and the remaining 40% are sent via E3. Of those sent via E2 only 2% arrive late, whereas 5% of the parcels handled by E3 arrive late. a. Draw a tree diagram for this problem. b. If a record of an overnight mailing is randomly selected from the company's file, what is the probability that the parcel went via E2 and was late? c. What is the probability that a randomly selected parcel arrived on time? d. If a randomly selected parcel has arrived late, what is the probability that is was not sent via El