Clough company is interested in establishing the relationship between utility costs and machine hours. data have been collected and a regression analysis prepared using excel. the monthly data and the regression output follow: month machine hours utility costs january 3,250 $ 22,080 february 3,770 25,200 march 2,470 16,200 april 4,030 27,600 may 4,940 33,900 june 4,290 26,400 july 5,330 29,700 august 4,550 27,300 september 2,600 18,600 october 4,810 31,200 november 6,110 37,200 december 5,460 33,300 required: (a.) what is the equation for utility costs using the high-low method? (b.) prepare an estimate of utility costs for a month when 3,000 machine hours are worked.