Answer:
Joshua statement is correct.
Step-by-step explanation:
Marginal cost:
Is the cost of producing a new unit.
Average Cost:


If the marginal cost of this plant is lower than their other plants, it can decrease his average cost by increasing the amount produced.
This increase in production decrease the impact of the fixed cost in the unit price. At more production the average cost will decrease. Because the variable cost keeps at the same value but the fixed cost per unit decrease.