Practice Exercises 1. The controller of Teton Industries has collected the following monthly expense data for use in analyzing the cost behavior of maintenance costs. Total Machine Hours 300 Month January February March Total Maintenance Costs $2,900 3,000 3,600 4,300 3,200 400 600 April 790 500 May June 4,500 800 Instructions (a) Determine the fixed-cost and variable-cost components using the high-low method. (b) Prepare a graph showing the behavior of maintenance costs, and identify the fixed- cost and variable-cost elements. Use 200 unit increments and $1,000 cost increments