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Given the following cost and activity observations for Smithson Company's utilities, use the high-low method to calculate Smithson's fixed costs per month. Round your final answer to the nearest dollar. Do not round interim calculations. G Cost Machine Hours January 9,700 February 18,200 March 12,400 April 15,100 Oa. $12.578 Ob. $10,062 Oc. $21,383 Od. $40,250 $26,500 38,700 28,000 30,600