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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 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:

Compute the predicted maintenance cost at $620$ hours of activity.

Answer is complete but not entirely correct.