The following is a list of various costs of producing sweatshirts. Classify each cost as either a variable, fixed, or mixed cost for units produced and sold. a. Electricity costs of $0.025 per kilowatt-hour. b. Warehouse rent of $6,000 per month plus $0.50 per square foot of storage used. c. Thread. d. Zip used in sweatshirts. e. Janitorial costs of $2,000 per month. f. Advertising costs of $10,000 per month. g. Plant manager salary. h. Color dyes for producing different colors of sweatshirts. i. Salary of the production supervisor. j. Straight-line depreciation on sewing machines. k. Patterns for different designs. Patterns typically last many years before being replaced. I. Maintenance costs for the company's sewing machine. The cost is $2,000 per year plus $0.001 for each machine hour of use. m. Property taxes on factory, building, and equipment. n. Cotton and polyester cloth. o. Hourly wages of sewing machine operators