National Express reports the following costs and expenses in June 2020 for its delivery service. Indirect materials $7,100 Drivers' salaries $16,200 Depreciation on delivery equipment 11,400 Advertising 4,900 Dispatcher's salary 5,790 Delivery equipment repairs 370 Property taxes on office building 890 Office supplies 760 CEO's salary 12,800 Office utilities 1,030 Gas and oil for delivery trucks 3,200 Repairs on office equipment 240 Determine the total amount of (a) delivery service (product) costs and (b) period costs. Delivery service (product) costs Period costs $