below: $7$ points

Month

July

August

september

october

Direct Labor Total Overhead

Hours

Assume that the overhead costs above consist of utilities, supervisory salaries, and

maintenance. The breakdown of these costs at the $9,000$ direct labor hour level of activity is

as follows:

Utilities $($V$)$

Supervisory Salaries

$($F$)$

Maintenance $($M$)$

$$137,700$

$80,000$

$101,300$

$$319,000$

Required:

$($a$)$ Using the high$-$low method, determine the cost formula for maintenance.

$($b$)$ Express the company's total overhead costs in linear equation form.