Arectangular prism has a height of 3 inches and a volume of 27 cubic inches the height of this prism is changed to 6 inches and the other dimensions stay the same what is the volume of the prism with this change

Ben frank is an electrician who installs lighting fixtures. he charges (in dollars) his clients 15h+40f15h+40f where hh is the number of hours worked and ff is the number of fixtures installed. how much does ben frank charge when he works 77 hours and installs 99 fixtures?