The following variable production costs apply to goods made by Stuart Manufacturing Corporation: Item Materials Labor Variable overhead. Total Cost per unit $14.00 2.50 0.25 $16.75 Required Determine the total variable production cost, assuming that Stuart makes 8,000, 18,000, or 28,000 units. Answer is complete but not entirely correct. Units Produced Total variable cost 8,000 18,000 28,000 114,000 256,500 399,000