A consumer who is in permanent debt is considering to buy an appliance with an expected lifetime of 5 years that costs $ 100. The label on the appliance indicates that it uses 100 kWh per year. The consumer's existing appliance is still working but uses 250 kWh per year. He is considering making the purchase but only has access to credit card financing at an interest rate of 20 % per year. Electricity where the consumer lives costs on average 20 cents/kWh. a. Calculate the payback period for this investment. (2) b. Calculate the discounted payback period of this investment.(3) c. Calculate the simple total rate of return on the investment. (2) d. What is the net present value?(3) e. What is the internal rate of return (IRR)? (3) f. Should the consumer buy the appliance? Explain. (2) What might affect her buying decision? (3) g