11. i need help with this problem for my corporate finace class. It would be much appriected if you can show me how you got the work!

The Fast Reader Company supplies bulletin board services to numerous hotel chains nationwide. The owner of the firm is investigating the desirability of employing a billing firm to do her billing and collections. Because the billing firm specializes in these services, collection float will be reduced by 16 days. Average daily collections are $12,600, and the owner can earn 8.4% annually (expressed as an APR with monthly compounding) on her investments. If the billing firm charges $500 per month, should the owner employ the billing firm? - Assuming the billing firm can reduce the collection float immediately, as soon as Fast Reader starts the service they will receive $ (Round to the nearest dollar.) The present value of the billing firm's charges is $ (Round to the nearest dollar.) Fast Reader employ the billing firm. (Select from the drop-down menu.)