Don and Patti, brother and sister, were together for Thanksgiving dinner with the rest of the family.Patti was explaining why she was not going to eat her previous favorite dish, creamed spinach, because of how much effort she was putting into eating healthier and being physically fit. As common with their relationship, her brother Don was cynical of Patti's latest claims about increasing her athletic skills. Don told Patti in front of everyone, "I will pay you five hundred dollars if you complete the twenty-six miles of the Central City Marathon being run next Sunday." Patti entered the race and, as she staggered past the twenty-five mile marker, Don yelled "I revoke my offer!" Patti heard Don's words, but she completed the marathon anyway. She demanded the five hundred dollars, but Don refused to pay.

Please answer both of the following:

1. Patti wants to go to small claims court to get her $500 and put an end to Don's cynicism once and for all. She comes to you, a family friend, and asks you to help her structure her legal argument. Please help Patti. You need to identify the kind of contract it is, bilateral or unilateral, and then prove, using the prima facie case, that the contract was properly formed, using all the elements of offer, acceptance and consideration, and that it was performed.
2. Don is served the small claims summons. He comes to you, a family friend, and asks you to help structure his defense. Please help Don structure his legal defense. What are his best arguments to counter Patti's arguments on the prima facie case for offer, acceptance, and consideration.