Nation's Capital Fitness, Incorporated, operates a chain of fitness centers in the Washington, D.C., area. The firm's controller is accumulating data to be used in preparing its annual profit plan for the coming year. The cost behavior pattern of the firm's equipment maintenance costs must be determined. The accounting staff has suggested the use of the high-low method to develop an equation, in the form of Y=a+bX, for maintenance costs. Data regarding the maintenance hours and costs for last year are as follows