Armer Company is accumulating data to use in preparing its annual profit plan for the coming year. The cost behavior pattern of the maintenance costs must be determined. The accounting staff has suggested the use of linear regression to derive an equation for maintenance hours and costs. Data regarding the maintenance hours and costs for the last year and the results of the regression analysis follow: Maintenance Month Cost Jan. $ 4,850 Feb. 3,650 Mar. 4,250 Apr. 3, 470 May 5,000 June 3,610 July 3,680 Aug. 5,120 Sept. 4,910 Oct. 4,700 Nov. 3,950 Dec. 3,810 Sum $51,000 Average $ 4,250 Average cost per hour a (intercept) b (coefficient) Standard error of the estimate R-squared t-value for b Machine Hours 740 580 660 560 760 570 580 840 750 730 610 600 7,980 $ 665 $ 6.00 $-78.2386 6.5086 114.5939 0.9695 92.950 The percent of the total variance that can be explained by the regression equation is