Required Identify each of the items shown in the left column of the following table as being an upstream, a midstream, or a downstream cost. The first item is shown as an example. Type of Cost Midstream Item Direct materials Research and development Product design Manufacturing overhead Sales salaries Cost of delivering merchandise to customers Cost to create a copyright Salaries of product engineers Salaries of production line workers Direct labor Cost to heat the manufacturing plant Advertising expenses Patent filing fees Salary of company president Depreciation on manufacturing equipment Depreciation on office equipment