Colby Limited is a manufacturing company whose total factory overhead costs fluctuate somewhat from year to year, according to the number of machine-hours worked in its production facility. These costs at high and low levels of activity over recent years are given below: Level of activity Machine-hours Total factory overhead costa Low 65,000 $31,420,000 High 75,000 $33,400,000 The factory overhead costs above consist of Indirect materials, rent, and maintenance. The company has analyzed these costs at the 65,000 machine-hours level of activity as follows: Indirect materials (variable) Rent (fixed) Maintenance (mixed) $8,970,000 15,000,000 7,450,000 Total factory overhead coats $31,420,000 For planning purposes, the company wants to break down the maintenance cost into its variable and fixed cost elements. Required: 1. Estimate how much of the factory overhead cost of $33,400,000 at the high level of activity consists of maintenance cost. Maintenance cost 2. Using the high-low method, estimate a cost formula for maintenance.