Mackey Publishing Company (Mackey) is a publisher of novels. The monthly equipment maintenance cost for Mackey is considered to be a mixed cost. The variable portion of the cost is related to the number of novels published. The production volume and maintenance costs for the past six months are presented below. Mackey uses the high-low method to separate mixed costs into its fixed and variable portions. Do not enter dollar signs or commas in the input boxes. a) Calculate the variable rate for the equipment maintenance cost. Variable Cost per Unit: $ b) Calculate the fixed portion of the equipment maintenance cost. Fixed Cost: $ c) Assume that 420,000 novels is the budgeted production level for June. Using the results of the high-low method in parts a) and b), what is the expected total equipment maintenance cost for June? Expected total equipment maintenance cost for June: $