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The fixed costs required to modify an existing production facility's layout is estimated to be $3,200,000. It is believed that the new layout will reduce the variable cost per unit associated with producing the product by $11.50 (from the current $24.50 per unit to $13.00 ). If the product sells for $21 per unit, what must dernand be in order for the modification to break even? The break-even quantity is units. (Enter your response as a whole number.)