Bus. Law Question!!! PLEASE HELP!?

AAA Delivery Service contracts to deliver Best Pizza Company's goods to its customers for $5,000, payable in advance. Best pays the money, but AAA fails to perform. Can Best rescind the contract? Can Best also obtain restitution? What does it mean to "rescind" a contract? How is a contract rescinded? What is restitution? How restitution accomplished? Explain.