National Express reports the following costs and expenses in June 2020 for its delivery service. $16,100 5,300 Indirect materials Depreciation on delivery equipment Dispatcher's salary Property taxes on office building CEO's salary Gas and oil for delivery trucks $7,200 12,300 5,940 920 420 Drivers' salaries Advertising Delivery equipment repairs Office supplies Office utilities Repairs on office equipment 690 1,020 12,900 2,500 240 Determine the total amount of (a) delivery service (product) costs and (b) period costs. Delivery service (product) costs $ Period costs $