Melissa recently paid $870 for round-trip airfare to San Francisco to attend a business conference for three days. Melissa also paid the following expenses: $400 fee to register for the conference, $260 per night for three nights' lodging, $120 for meals in restaurants, and $425 for cab fare.

Note: Do not round intermediate calculations. Round your final answers to the nearest whole dollar amount. Leave no answers blank. Enter zero if applicable.

a. What amount of these costs can Melissa deduct as business expenses?

b. Suppose that while Melissa was on the coast, she also spent two days sightseeing the national parks in the area. To do the sightseeing, she paid $1,010 for transportation, $1,055 for lodging, and $495 for meals during this part of her trip, which she considers personal in nature. What amount of the total costs can Melissa deduct as business expenses?

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?

d. Suppose that Melissa's permanent residence and business were located in San Francisco. She attended the conference in San Francisco and paid $400 for the registration fee. She drove 117 miles over the course of three days and paid $111 for parking at the conference hotel. In addition, she spent $595 for breakfast and dinner over the three days of the conference. She bought breakfast on the way to the conference hotel, and she bought dinner on her way home each night from the conference. What amount of these costs can Melissa deduct as business expenses?