The estimates for three alternatives are to be compared on the basis of their perpetual equivalent annual worth. At an interest rate of 10% per year, what is the AW of Z1? Alternative X1 Y1 Z1 First Cost -55,000 -87,000 -64,000 Annual Cost -9,300 -4,300 -8,000 Salvage Value -11,000 14,365 17,783 Life Years 3 6 9 -34,740 -23,049 -22,414 -18,303 -17,803