Oscar is a motor mechanic who operates a garage. Inside his garage a sign reads “owners liability at own risk, please do not enter.” He decides to offer half-price tune-ups to regular customers to reward their loyalty and identifies his 50 most regular customers from his records and mails the offer to them, addressed to: “Dear Valued Regular Customer”. Oscar’s letter states the discount will be available to anyone replying within two months of the date of the letter
