E22-2 (b) The controller of Dugan Industries has collected the following monthly expense data for use in analyzing the cost behavior of maintenance costs. Month Total Maintenance Costs Total Machine Hours January $2,400 300 February 3,000 400 March 3,600 600 April 4,500 790 May 3,200 500 June 4,900 800 Instructions Prepare a graph showing the behavior of maintenance costs, and identify the fixed and variable cost elements. Use 200 unit increments and $1,000 cost increments