Listed below are costs of providing an airline service. Classify each cost as (a) either variable or fixed, and (b) either direct or indirect by selecting the appropriate dropdowns. Consider the cost object to be a flight. Flight attendants and pilots are paid based on hours of flight time. Variable or Fixed Direct or Indirect Cost 1. Advertising 2 Beverages served on planes 3. Regional vice president salary 4. Depreciation (straight-line) on ground equipment 5. Fuel used in planes 6. Flight attendant wages 7. Plot wages 8. Aircraft maintenance manager salary