National Express reports the following costs and expenses in Jun 2017 for its delivery service $16,200 5,400 400 760 1,030 210 Advertising Delivery equipment repairs Depreciation on delivery equipment Dispatcher's salary Property taxes on office building CEO's salary Gas and oil for delivery trucks 11,400 5,710 910 Office supplies 12,900Office utilities 3,200 Repairs on office equipment Determine the total amount of (a) delivery service (product) costs and (b) period costs