High-Low and Cost Formula Harrison Company has accumulated the following total manufacturing overhead costs for two levels of activity (within the relevant range): Low High Activity (direct labor hours) 80,000 120,000 Total manufacturing overhead $936,000 $1,208,000 The total overhead cost includes variable, fixed, and mixed costs. At 120,000 direct labor hours, the total cost breakdown is as follows: Variable cost $528,000 320,000 Semi-mixed cost $360,000 Fixed cost