Minimizing cruise line costs deluxe river cruises operates a fleet of river vessels. the fleet has two types of vessels: a type a vessel has 60 deluxe cabins and 160 standard cabins, whereas a type b vessel has 80 deluxe cabins and 120 standard cabins. under a charter agreement with the odyssey travel agency, deluxe river cruises is to provide odyssey with a minimum of 360 deluxe and 680 standard cabins for their 15-day cruise in may. it costs $44,000 to operate a type a vessel and $54,000 to operate a type b vessel for that period. a. how many of each type of vessel should be used to keep the operating costs to a minimum? b. find the range of values that the cost of operating a type a vessel can assume without changing the optimal solution. c. find the range of values that the requirement for deluxe cabins can assume. d. find the shadow price for the requirement for deluxe cabins.