How do i solve for the volume of a rectangular prism if the height is not known?

An architect is designing a water fountain for a park she uses the given function to model the water jet flowing from the fountain nozzles where h(x) gives the height of the water jugs in feet x feet from the starting point h(x)=-1/20x+x+15

If the class was going to get a class pet and 5 picked fish and 7 pick bird and 8 picked rabbits have many students were in the

What are the exclude value of mn+3m