Adam wants to sell his car for $60,000. He posts a picture of the car on Facebook and Twitter with a sales price of $65,000. Beryl sees the advertisement on Facebook and offers to buy the car for $50,000. Adam refuses. The next day Colin contacts him via Twitter and offers him $60,000. He accepts the offer and the day after that, accepts and deposits a cheque from Colin in the amount of $60,000. Two days later Beryl contacts him and offers him the $65,000 for the car. Adam is shocked but wants to get the $5000 extra from the sale to Beryl. Adam tells Colin that he changed his mind and that he will give him a cheque for the $60,000. Does Colin have a valid contract that he can enforce?

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