In the Waterway, maintenance costs are a mixed cost. At the low level of activity (120 direct labor hours), maintenance costs are $1500. At the high level of activity (500 direct labor hours), maintenance costs are $2750. Using the high-low method, what is the variable maintenance cost per unit and the total fixed maintenance cost? Variable Cost Per Unit Total Fixed Cost $3.29 $1250 $5.50 $330 O $3.29 $1105 O $5.50 $3500