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OROK currently makes all sales on credit and offers no cash discount. The fim is considering a 3 percent cash discount for payment within 15 days. Its current average collection period is 50 days, sales are 2,000 films per year, selling price is $45 per film, and the variable cost is $35 per film. ROK expects that the change in credit terms will result in an increase in sales to 2,200 films, of which 70 percent of the sales will take the discount. Then, the average collection period will drop to 30 days. The firm's bad debt expense is expected to become negligible under the proposed plan Its required return on equal-risk investments is 15 percent. What is the firm's additional (marginal) profit contribution from sales under the proposed a. plan of initiating the cash discount? b. What is the additional investment in accounts receivable with the proposed change? c. What is the cost (-) or benefits (+) of additional investments in ARs under the proposed plan? d. What is the total cost of offering the cash discount