QS 21-2 Cost behavior identification LO C1 Identify whether each of the following is best described as a fixed, variable, or mixed cost with respect to product units. Variable 1 Rubber used to manufacture athletic shoes 2. Maintenance of factory machinery 3. Packaging expense 4 Wages of an assembly-line worker paid on the basis of acceptable unlts produced 5. Factory supervisor's salary 6. Taxes on factory building 7 Depreciation expense of warehouse