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Variance I : Assigned Problems 1. The per-unit standards for direct materials are 2 gallons at $4 per gallon. last month, 5,600 gallons of direct materials that actually cost $21,200 were used to produce 3,000 units of product. The direct materials quantity variance for last month was a. $1,600 favorable. b. $1,200 favorable. 0. $1,600 unfavorable. (1. $2,800 unfavorable. e. None of the above