Martha's Vineyard Marine Supply is a wholesaler for a large variety of boating and fishing equipment. The company's controller, Mathew Knight, has recently completed a cost study of the firm's material-handling department in which he used work measurement to quantify the department's activity. The control factor unit used in the work-measurement study was hundreds of pounds of equipment unloaded or loaded at the company's loading dock. Knight compiled the following data. Units of Activity (hundreds of pounds of Material-Handling Month equipment loaded or unloaded) Department Costs January 2,900 $25, 470 February 2,700 24, 910 March 2,600 24, 330 April 4,100 29, 600 May 3,300 26, 640 June 3,500 27 , 800 July 3,900 29, 470 August 3,700 27 , 460 September 2,500 23, 200 October 2, 800 25, 090 November 3,100 25, 980 December 3,300 26,940 Required: 5. Estimate the material-handling department's cost behavior using the high-low method. Use an equation to express the results of this estimation method. (Round coefficient of X to 2 decimal places.) Material-handling cost per month = X