Please explain C for me!

Sarasota Vita produces a wide range of herbal supplements sold nationwide through independent distributors. response to an increasing demand for its products, the company is considering the purchase of a new packaging machine to replace the seven- year-old machine currently in use. The new machine will cost $168,800, and installation will require an additional $3,125. The machine has a useful life of 10 years and is expected to have a salvage value of $3,940 at that time. The variable cost to operate the new machine is $10.90 per carton compared to the current machine's variable cost of $11.00 per carton, and Sarasota Vita expects to pack 252,000 cartons each year. If the new machine is purchased, Sarasota Vita will avoid a required $10,800 overhaul of the current machine in four years. The current machine has a market value of $12,700. Click here to view the factor table. (a) Calculate the net present value of the new packaging machine. Assume that Sarasota Vita uses an 8% discount rate. (For calculation purposes, use 4 decimal places as displayed in the factor table provided and round final answer to 2 decimal places, e.g. 58,971.75. Enter negative amount using a negative sign preceding the number, e.g. -59,991 or parentheses e.g. (59,991).) Net present value $ 19629 (b) Do you recommend that Sarasota Vita purchase the new machine? Yes (b) Do you recommend that Sarasota Vita purchase the new machine? Yes (c) Assume that Sarasota Vita has adopted a new 11% discount rate. Calculate the net present value of the new packaging machine. (For calculation purposes, use 4 decimal places as displayed in the factor table provided and round final answer to 2 decimal places, e.g. 58,971.75. Enter negative amount using a negative sign preceding the number, e.g.-59,991 or parentheses e.g. (59,991).) Net present value $ 171925.00 Do you recommend that Sarasota Vita purchase the new machine? No eTextbook and Media Save for Later Attempts: 2 of 3 used Submit