Nova Company's total overhead cost at various levels of activity are presented below: Honth April Total Overhead Cost Machine-Hours 48,000 $ 185,880 38,000 58,000 68,000 $ 160,780 $ 210,980 May June July $ 236,080 Assume that the total overhead cost above consists of utilities, supervisory salaries, and maintenance. The breakdown of these costs at the 38,000 machine-hour level of activity is: Utilities (variable) Supervisory salaries (fixed) Maintenance (mixed) Total overhead cost $ 49,400 47,000 64,380 $ 160,780 Nova Company's management wants to break down the maintenance cost into its variable and fixed cost elements. Required: 1. Estimate how much of the $236,080 of overhead cost in July was maintenance cost. (Hint: to do this, it may be helpful to first determine how much of the $236,080 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 company's total overhead cost in the form Ya+bX 4 4. What total overhead cost would you expect to be incurred at an activity level of 43,000 machine-hours