In the Crane, maintenance costs are a mixed cost. At the low level of activity (90 direct labor hours), maintenance costs are $900. At the high level of activity (400 direct labor hours), maintenance costs are $2200. Using the high-low method, what is the variable maintenance cost per unit and the total fixed maintenance cost? Variable Cost Total Fixed Per Unit Cost $4.19 $523 $5.50 $1800 O $4.19 $1300 o $5.50 $248