D Question 15 The following information is available for a company's utility cost for operating its machines over the last four months. Month Machine hours Utility cost January 910 $ 6,460 February 1,810 $ 6,920 March 2,420 $ 8,100 April 610 $ 4,580 Using the high-low method, the estimated variable cost per machine hour for utilities is: $6.27. $1.94 $3.35, $7.51. $4.53