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 regarding the maintenance hours and costs for the last year and the results of the regression analysis follow Month must be determined. The accounting staff has suggested the use of linear regression to derive an equation for maintenance hours and costs. Data Maintenance Cost $4,200 3,000 3,600 2,820 4,350 2,960 3,030 4,470 4,260 4,050 3,300 Machine Hours 480 320 400 300 500 Feb Mar Apr May une July Aug Sept Oct Nov Dec Sum Average Average cost per hour a (intercep b (coefficient) Standard error of the estimate R-squared t-value for b 320 490 350 $43,200 $3,600 4800 400 $9.00 684.65 2884 34 469 0.99724 60.1 The coefficient of determination for Armer's regression equation for the maintenance activities is