Answer: variable costs will remain at $12.00 per unit
Step-by-step explanation:
Variable costs refers to the costs that change when there's a change in the quantity of the good that's produced.
Since when 24,000 units are produced, the variable costs are $12.00 per unit. It should be noted that even when 18,000 units are produced, the variable cost will still remain $12.00 per unit.