you have an autographed CD by Drake and put it up for sale on eBay. So far, the highest bid is $74.50. A friend has offered you $100 for the CD, commenting that he could get $150 for it on eBay in a year. You know this is highly unlikely. Should you sell your friend the CD for what he offered ($100)? Do you have an obligation to tell your friend you have listed your CD on eBay?