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22. If the LHK Company had a per unit cost that was $5 when 400 units were produced and a per unit cost of $4 when 500 units were produced, the cost is a A. Mixed cost of $5 per unit variable cost and $400 fixed cost B. Variable cost of $5 per unit C. Fixed cost of $2,000 D. Mixed cost of $4 per unit variable cost and $400 fixed cost