Seth Fitch owns a small retail ice cream parlor

Seth Fitch owns a small retail ice cream parlor. He is considering expanding the business and has identified two attractive alternatives. One involves purchasing a machine that would enable Mr. Fitch to offer frozen yogurt to customers. The machine would cost $16,200 and has an expected useful life of three years with no salvage value. Additional annual cash revenues and cash operating expenses associated with selling yogurt are expected to be $12,400 and $1,800, respectively. Alternatively, Mr. Fitch could purchase for $20,160 the equipment necessary to serve cappuccino. That equipment has an expected useful life of four years and no salvage value. Additional annual cash revenues and cash operating expenses associated with selling cappuccino are expected to be $17,000 and $4,860, respectively. 
Income before taxes earned by the ice cream parlor is taxed at an effective rate of 20 percent. 
Required Round your figures, including percentage rates, to two decimal points. a. Determine the payback period and unadjusted rate of return (use average investmeM) for each alternative. b. Indicate which investment alternative you would recommend. Explain your choice.