Discuss and use various methods to estimate the variable and fixed costs portions of a mixed cost

Using activity analysis, Arnoldson Company has identified the appropriate cost driver for maintenance costs in a factory as the number of machine hours. The maintenance costs have been observed as follows within the relevant range of 5,000 to 8,000 machine-hours.

Month                Maintenance Cost         Machine Hours

January                        $7,900                                5,600

February                      $8,500                                7,100

March                          $7,400                                5,000

April                             $8,200                                6,500

May                              $9,100                                7,300

June                              $9,800                                8,000

July                               $7,800                                6,200

Required:

1. Estimate the cost function using the high-low method.

2. If you were going to use the visual-fit method to estimate the cost function, what steps will you take?