Shown below are units produced and total manufacturing costs for the past four months at Minga Manufacturing Corporation: Units Produced Total Cost Jul 120 $446,000 Aug $508,000 Sep $668,000 Oct 160 $574,000 What is Minga's cost formula for total manufacturing cost under the high-low method? Select one: a. Y = $14,000 + $3,600X b. Y = $3,700 + $2,000x c. Y = $62,000 + $3,200x d. Y = $2,000 + $3,700X