A natural gas well is being drilled in your community. It is estimated that amount of recoverable natural gas is equivalent to 5 MCF and that your community will use this fuel at an initial rate of 0.4 MCF/year, selling an additional 0.6 MCF/year back to the utility. Assuming that the annual rate of increase in consumption will be at 2%, determine how long (in years) it will take to exhaust this natural gas well