1. Joe, a university student, parked his car near Harry's garage and went away to attend classes. Harry had noticed that there was glass on the street when he came to work that morning and was not surprised when he saw that several of the students' cars parked in that location subsequently had flat tires. He went around when he had time during the day, to each of those cars, fixed the tires and put a bill on each vehicle charging $15 for the service. Joe had come back during the day and noticed his flat tire, and when he came back that evening was grateful that it had been fixed. He went over to the garage to thank Harry and told him that he would be happy to pay the $15, but he couldn't do it until next week. In fact, he failed to pay the money, and Harry sued him for breach of contract. Explain the likely outcome.

1. Hank rented a new ground-floor condominium for four months before the owner offered to sell it to him. Hank accepted the offer. After Hank became the owner, he built a small patio off the living room. At a house-warming party, one of his friends caught the heel of her shoe between some patio bricks and fell, breaking her arm. It took an abnormally long time to heal because she suffered from an unusual bone disease. What was Hank's liability in this case? Can his friend sue him?