9. Aubie Manufacturing Company produces inventory in a highly automated assembly plant in Auburn, Alabama. The automated system is in its first year of operation and management is still unsure of the best way to estimate the overhead costs of operations for budgetary purposes. For the first six months of operations, the following data were collected: Machine-hours Kilowatt-hours Total Overhead Costs January 4,560 5,424,000 $405,600 February 4.380 5,208,000 404,160 March 4,680 5,400,000 407,040 April 3,960 5,148,000 404,160 May 3,900 5,040,000 391,200 June 3,720 4.944,000 384,000 a Required: (6 points) Use the high-low method to determine the estimating cost function with machine-hours as the cost driver. b. Use the high-low method to determine the estimating cost function with kilowatt-hours as the cost driver. BONUS: For July, Aubie ran the machines for 4,050 hours and used 4,495,000 kilowatt-hours of power. The overhead costs totaled $365,000. Which cost driver was the best predictor for July