If you insulate your office for $1,000, you will save S1,100 a year in heating expenses. These savings will ast forever. a. What is the NPV of the investment when the cost of capital is 8%710%? Cost of 8% 10% CapitalNPV b. What is the IRR of the investment? (Enter your answer as a whole percent.) c. What is the payback period on this investment? period