Alyeski Tours operates day tours of coastal glaciers in Alaska on its tour boat the Blue Glacier. Management has id$$ntified two cost drivers$-$the number of cruises and the number of passengers$-$that it uses in its budgeting and performance reports. The company publishes a schedule of day cruises that it may supplement with special sailings if there is sufficient demand. Up to $85$ passengers can be accommodated on the tour boat. Data concerning the company's cost formulas appear below:

$\backslash$table$[[,$Fixed,,$],[,$Cost per Cost per Cost per,,$],[$Month$,$Cruise,Passenger,$],[$Vessel operating costs,$$6,800,$$$478\mathrm{.}00,$$$3\mathrm{.}00$