If you insulate your office for $16,000, you will save $1,600 a year in heating expenses. These savings will last forever. a. What is the NPV of the investment when the cost of capital is 5%? 10%? ... b. What is the IRR of the investment? (Enter your answer as a whole percent.) IRR= ?? % c. What is the payback period on this investment? Payback Period= ?? Years