A firm is comparing two investment opportunities, G and H. Project G costs $1,500 and yields $700 annually for 4 years. Project H costs $1,200 and yields $650, $600, $500, and $400 over the next 4 years.

1. Calculate the NPVs of projects G and H using a 10% discount rate.
2. Find the internal rate of return (IRR) for each project.
3. Discuss which project should be selected if the required rate of return is 10%.
4. Illustrate the sensitivity of the NPV to changes in the discount rate.