ova Companys total overhead cost at various levels of activity are presented below: Month Machine- Hours Total Overhead Cost April 49,000 $ 199,830 May 39,000 $ 173,130 June 59,000 $ 226,530 July 69,000 $ 253,230 Assume that the total overhead cost above consists of utilities, supervisory salaries, and maintenance. The breakdown of these costs at the 39,000 machine-hour level of activity is: Utilities (variable) $ 58,500 Supervisory salaries (fixed) 55,000 Maintenance (mixed) 59,630 Total overhead cost $ 173,130 Nova Companys management wants to break down the maintenance cost into its variable and fixed cost elements. Required: 1. Estimate how much of the $253,230 of overhead cost in July was maintenance cost. (Hint: to do this, it may be helpful to first determine how much of the $253,230 consisted of utilities and supervisory salaries. Think about the behavior of variable and fixed costs.) 2. Using the high-low method, estimate a cost formula for maintenance in the form Y = a + bX. 3. Express the companys total overhead cost in the form Y = a + bX. 4. What total overhead cost would you expect to be incurred at an activity level of 44,000 machine-hours?