Required information [The following information applies to the questions displayed below.] Melissa recently paid $800 for round-trip airfare to San Francisco to attend a business conference for three days. Melissa also paid the following expenses: $510 fee to register for the conference, $400 per night for three nights' lodging, $220 for meals, and $445 for cab fare. (Leave no answers blank. Enter zero if applicable. Do not round intermediate calculations. Round your final answer to the nearest dollar amount.) c. Suppose that Melissa made the trip to San Francisco primarily to visit the national parks and only attended the business conference as an incidental benefit of being present on the coast at that time. What amount of the airfare can Melissa deduct as a business expense? Deductible amount