Classifying Cost Behavior Classify the total costs of each of the following as variable, fixed, mixed, or step. a. S traight-line depreciation on a building b. Maintenance costs at a hospital c. R ent on a photocopy machine charged as a fixed amount per month plus an additional charge per copy d. Cost of goods sold in a bookstore e. S alaries paid to temporary instructors in a college as the number of course sessions varies f. L umber used by a house construction company g. The costs of operating a research department h. The cost of hiring a dance band for three hours i. L aser printer paper for a department printer j. E lectric power in a restaurant