The controller of Crane Industries has collected the following monthly expense data for use in analyzing the cost behavior of maintenance costs. Total Machine Hours Total Maintenance Costs $2,590 2.890 3,490 4,390 3,090 4,790 Month January February March April May June 330 380 530 660 530 730 (a1) Determine the variable cost components using the high-low method. (Round answer to 2 decimal places e.g. 225.) Variable cost per machine hour $