In the spring a young maple is 18 feet tall. over the summer it grows 8%. how tall is the maple at the end of the summer? do not include units in your answer.

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?