Which of the following should not be included as a cash flow in evaluating an investment project that involves offering a new product for the firm? Revenue in the future from sales of an existing product to new customers brought into the firm by the introduction of the new product Future costs of marketing the new product that you plan to introduce. Costs of developing and testing the new product that have already been incurred and paid. Future wages and salaries for current employees of the firm who will be assigned to work on the new project