A small company heats its building and will spend $9,240 in year 1 on natural gas for this purpose. Cost increases of natural gas are expected to be 10% per year starting year 2. Their maintenance on the gas furnace is going to be $380.80 in the first year and this expense is expected to increase by 12% per year starting year 2. If the planning horizon is 15 years, what is the total annual equivalent oxpense for operating and maintaining the fumace? The interest rate is 18% per year. (6) The total present worth of operating and maintaining the tumace is $(Round to nearest dolar) (1) The total arnual equivalent expense for operating and maintaining the furnace is $])(Round to rearost dollar) fore yo