The new dolphin tank at the city aquarium is in the shape of a rectangular prism. It is long by wide by deep. To make the tank livable for the dolphins, the aquarium workers treat the water using bags of salt. The amount of water a bag of salt can treat is known in cubic feet. (a) Find the volume of water in the tank in cubic feet.

(b) To make the tank livable for the dolphins, a bag of salt must be added for each 19.4ft$ of water. The aquarium doesn't have any salt on hand and the salt can only be purchased in whole bags. How many bags of salt must be purchased to treat the water?
(c) If each bag of salt costs $4.85, how much must the aquarium pay for salt to treat all the water in the new dolphin tank?
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