Rapid Delivery Service reports the following costs and expenses in June 2011. Indirect materials $ 6,300 Drivers' salaries $11,900 Depreciation on delivery equipment 12,300 Advertising 2,300 Dispatcher's salary 5,300 Delivery equipment repairs 500 Property taxes on office building 960 Office supplies 690 CEO's salary 13,100 Office utilities 1,010 Gas and oil for delivery trucks 3,100 Repairs on office equipment 200 Determine the total amount of (a) delivery service (product) costs and (b) period costs. Delivery service (product) costs $