Brenda placed an advertisement in a newspaper that said: "Five goldfish for sale. $2 each. First, come/first served. Please respond in person or by sending an email" Nathan saw the advertisement and immediately sent an email message that said: "I will pay $10 for the five goldfish." However, when Nathan arrived at Brenda's door with the cash in hand, she refused to hand over the goldfish. She explained that while Nathan's message was the only reply that she had received in response to her advertisement, she had changed her mind and had decided to keep the goldfish for herself. Provide an argument on behalf of Nathan that would support the creation of a contract with Brenda.