The city of Columbia is considering extending the runways of its municipal
airport so that commercial jets can use the facility. The land necessary for the
runway extension is currently a farmland that can be purchased for $350,000.
Construction costs for the runway extension are projected to be $600,000, and
the additional annual maintenance costs for the extension are estimated to be
$22,500. If the runways are extended, a small terminal will be constructed
at a cost of $250,000. The annual operating and maintenance costs for the
terminal are estimated at $75,000. Finally, the projected increase in flights