please post with details, and what equations were used ( excel )

The city of Peachtree is comparing the following two plans for supplying water to a newly developed subdivision: Plan A: will manage requirements for the next 15 years; at the end of that period, the initial cost of $1,500,000 will have to be doubled to meet the requirements of subsequent years. The facilities installed in years 0 and 15 may be considered permanent; however, certain supporting equipment will have to be replaced every 30 years from the installation dates at a cost of $200,000. Operating costs are $91,000 a year for the first 15 years and $182,000 thereafter. Beginning in the 21st year, they will increase by $3,000 a year. Plan B: will supply all requirements for water indefinitely into the future, although it will operate at only half capacity for the first 15 years. Annual costs over this period will be $105,000 and will increase to $155,000 beginning in the 16th year. The initial cost of Plan B is $1,950,000; the facilities can be considered permanent, although it will be necessary to replace $350,000 of equipment every 30 years after the initial installation. The city will charge the subdivision the use of water calculated on the equivalent annual cost. At an interest rate of 10%, determine the equivalent annual cost for each plan and make a recommendation to the city as to the amount that should be charged to the subdivision. Each house in the subdivision consumes 200 cubic meters per year. A subdivision has 50 homes