Nova Company$$s total overhead cost at various levels of activity are presented below: Month Machine$-$Hours Total Overhead Cost April $46,000$ $ $178,800$ May $36,000$ $ $152,800$ June $56,000$ $ $204,800$ July $66,000$ $ $230,800$ Assume that the total overhead cost above consists of utilities, supervisory salaries, and maintenance. The breakdown of these costs at the $36,000$ machine$-$hour level of activity is: Utilities $($variable$)$ $ $54,000$ Supervisory salaries $($fixed$)47,000$ Maintenance $($mixed$)51,800$ Total overhead cost $ $152,800$ Nova Company$$s management wants to break down the maintenance cost into its variable and fixed cost elements. Required: $1.$ Estimate how much of the $$230,800$ of overhead cost in July was maintenance cost. $($Hint: to do this, it may be helpful to first determine how much of the $$230,800$ 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 Y $=$ a $+$ bX$.4.$ What total overhead cost would you expect to be incurred at an activity level of $41,000$ machine$-$hours?