Andy went shopping and saw that there were games on sale in a computer center. Andy came to Patricks store, where there was a crowd. Andy took much effort to get into the store and found the Hunter. Andy quickly picked up two boxes of the Hunter from a table in which there was a poster stated Summer Sale. Everything must go. Andy however could not find any price tag on either of the boxes. Andy asked Patrick, the shop owner, for the price of the computer games. Busy chatting with other customers, Patrick turned his head, and said that $2,500 each, so just $5,000. Andy replied: How about $3,000? Patrick replied disinterestedly: No way. Andy then put down one box of the Hunter, and tendered the other box and $2,500 to Patrick. Patrick accepted the payment. It was at 3:00 pm.

From the contract law, advise Andy if there is any contract between him and Patrick for the sale and purchase of the box of Hunter at 3:00 pm;