Alyeski Tours operates day tours of coastal glaciers in Alaska on its tour boat the Blue Glacier. Management has identified 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 $81$ passengers ci be accommodated on the tour boat. Data concerning the company's cost formulas appear below:

$\backslash$table$[[,$Fixed Cost Cost per,Cost per,$],[,$per Month,Cruise,Passenger$],[$Vessel operating costs,$$6,600,$$$476\mathrm{.}00,$$$3\mathrm{.}50$