Scenario # $1$: Before Maria starts her first year of college, Fred promises to pay her $$5,000$ when she graduates. She goes to college, borrowing and spending far more than $$5,000.$ At the beginning of the spring semester of her senior year, she reminds Fred of the promise. Fred sends her a note that says, $$I revoke the promise.$$ Is Fred$$s promise binding? Explain.

Scenario # $2$: Sun Airlines, Inc., prints on its tickets that it is not liable for any injury to a passenger caused by the airline$$s negligence. If the cause of an accident is found to be the airline$$s negligence, can it use the clause as a defense to liability? Why or why not?