1.) What is the present value (PV) of an investment that will pay $ 300 in one year's time, and $ 300 every year after that, when the interest rate is 5%?

4.) Emma runs a small factory that needs a vacuum oven for brazing small fittings. She can purchase the model she needs for $180,000 up front, or she can lease it for five years for $4200 per month. She can borrow at 7% APR, compounded monthly. Assuming that the oven will be used for five years, should she purchase the oven or should she lease it?