Microbiotics currently sells all of its frozen dinners cash on delivery but believes it can increase sales by offering supermarkets 1 month of free credit. The price per carton is $100, and the cost per carton is $65. The unit sales will increase from 1,200 cartons to 1,260 per month.

a.	If the interest rate is 1% per month, and all customers will pay their bills, calculate the present value of per carton. (Do not round intermediate calculations. Round your answer to 2 decimal places.)

Present value

$ per carton

b.	If the interest rate is 1.5% per month, and all customers will pay their bills, calculate the present value of per carton. (Do not round intermediate calculations. Round your answer to 2 decimal places.)

Present value

$ per carton

c.

If the interest rate is 1.5% per month but the firm can offer the credit only as a special deal to new customers, while old customers will continue to pay cash on delivery. What will be the change in the firm's total monthly profits on a present value basis under these conditions? (Do not round intermediate calculations. Round your answer to 2 decimal places.)

Present value

$