A line graph showing the interaction of marginal cost, average total cost, demand, and marginal revenue."??? A graph with lines for marginal cost, average total cost, demand, and marginal revenue.??? The x-axis is labeled Quantity (units per hour).??? The y-axis is labeled Price or Cost (per unit).??? At 3 units per hour, marginal cost is between $4 and $5 per unit, average total cost is $6 per unit, demand is $10 per unit, and marginal revenue is $8 per unit.??? At 4 units per hour, marginal cost is $6 per unit, average total cost is $6 per unit, demand is $9 per unit, and marginal revenue is $6 per unit.??? At 5 units per hour, marginal cost is $8 per unit, average total cost is between $6 and $7 per unit, demand is $8 per unit, and marginal revenue is $4 per unit.??? At 6 units per hour, marginal cost is $10 per unit, average total cost is $7 per unit, demand is $7 per unit, and marginal revenue is between $2 and $3 per unit." Refer to the figure. If this monopolist were forced to behave as if it operated in perfect competition, the profit-maximizing rate of output would