19. Edward’s experience shows that 7% of the parcels he mails will not reach their destination. He has bought two books for $20 each and wants to mail them to his brother. If he sends them in one parcel, the postage is $5.20, but if he sends them in separate parcels, the postage is $3.30 for each book. To minimize the expected value of his expenses (loss + postage), which way is preferable to send the books, as two separate parcels or as a single parcel?