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As an Engineer, you are asked to consider two building proposals, which alternative do you deem superior based on the economics? (Assume the money to be used would be borrowed and paid back Within the life of the structure). The nominal interest rate is at 21.4% compounding quarterly. State which method you will use and state why. ALTERNATIVE A ALTERNATIVE B Steel Cement Life 20 years 20 years Initial Cost $1089 $2954 Maintenance $486/year $138/year Cost at the end of 8 $57 years