Family furniture corporation incurred the following costs. identify the costs as variable, fixed, or mixed. 1. wood used in the production of furniture. select a type of the costs 2. fuel used in delivery trucks. select a type of the costs 3. straight-line depreciation on factory building. select a type of the costs 4. screws used in the production of furniture. select a type of the costs 5. sales staff salaries. select a type of the costs 6. sales commissions. select a type of the costs 7. property taxes. select a type of the costs 8. insurance on buildings. select a type of the costs 9. hourly wages of furniture craftsmen. select a type of the costs 10. salaries of factory supervisors. select a type of the costs 11. utilities expense. select a type of the costs 12. telephone bill.