13 CES Required information Problem 6-42 Continuation of Preceding Problem; Computing Least-Squares Regression Estimates; Comparing Multiple Methods (Appendix) (LO 6-1, 6-2, 6-5, 6-6, 6-9) [The following information applies to the questions displayed below.] 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 equipment loaded or unloaded) Material-Handling Department Costs: Month January 2,900 $12,800 February 2,700 12,400 March 2,400 11,800 April 2,100 11,300 May 3,300 12,200 June 3,500 14,200 July 3,100 13,100 August 2,900 12,500 September 3,700 13,440 October 2,200 11,600 November 2,300 12,450 December 2,500 12,450