Hardly Normal Pty Ltd, a vendor of electronic equipment, advertised:

"NEVER TO BE REPEATED OFFER. 50in PANASONIC PLASMA 3D TELEVISIONS @ $7,500"

Ben saw the advertisement and the next day (Thursday) went to the store and said to Mary, the sales manager:

"I accept the offer on the plasma 3D TV - here is my card - please deliver it as soon as possible".

Mary told him to slow down. "Unfortunately, there has been a rush and we've sold out", she said. "Look", said Ben, "I know my business law - we've got a contract". Mary told him he was a young fool but went on to say:

"The only 3D plasma left is the demonstration model, and you can have that for $6,000. Not a bad price as they usually sell for around $7,500. That should make you happy".

Ben was not sure and said that he would think about it and let her know by noon the next day (Friday). Mary said she would definitely keep it for him until then. However, at 9.00 am on Friday Jin Tao walked into the store, saw the demonstration model, and offered Mary $6,500 for it. Mary sold it to her. At 10.00 am on Friday, Ben rang Mary and told her that he would buy the demonstration set at the price she offered. Mary then told him the bad news - the set had been sold.

Ben comes to your law office and seeks your advice as to whether a contract has been formed on either Thursday or Friday. Advise him whether a contract has been formed.