Clearup placed an advertisement in a magazine:

Clearup is guaranteed to work on problem skin. Use it according to the instructions for 3

months and experience a clear skin. If this does not happen we'll refund your money and pay

you $50.

Martin read the advertisement, purchased a three-month supply being 3 tubes at $10.00 each

and used it according to the instructions. At the end of the period, his skin was worse.

Explain whether there was an offer between Martin and Clearup that he can make a claim

under.