4. Jake is a professional dog trainer who purchases and trains dogs for use by law enforcement agencies. Last year Jake purchased 500 bags of dog food from a large pet food company at an average cost of $30 per bag. This year, however, Jake purchased 500 bags of dog food from a local pet food company at an average cost of $45 per bag. Under what circumstances would the IRS likely challenge the cost of Jake’s dog food as unreasonable?