(NPV with varying required rates of return) Gubanich Sportswear is considering building a new factory to produce aluminum baseball bats. This project would require an initial cash outlay of $4,000,000 and would generate annual free cash inflows of $1,200,000 per year for 8 years. Calculate the project's NPV given: a. A required rate of return of 7 percent b. A required rate of return of 12 percent c. A required rate of return of 14 percent d. A required rate of return of 18 percent