Asmall company heats its building and spends $8 comma 2008,200 per year on natural gas for this purpose. cost increases of natural gas are expected to be 99% per year starting one year from now (i. e., the first cash flow is $8 comma 9388,938 at eoy one). their maintenance on the gas furnace is $345345 per year, and this expense is expected to increase by 1212% per year starting one year from now (i. e., the first cash flow for this expense is $386.40386.40 at the eoy one). if the planning horizon is 1313 years, what is the total annual equivalent expense for operating and maintaining the furnace? the interest rate is 1515% per year.