In rough water, a small sand dollar burrows -1/2 centimeter into the sand. a larger sand dollar burrows -1 1/4 centimeters into the sand. which sand dollar burrowed farther?

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?