The AAA Aquarium Co. sells aquariums for \(\$ 20\) each. Fixed costs of production are \(\$ 20 .\) The total variable costs are \(\$ 20\) for one aquarium, \(\$ 25\) for two units, \(\$ 35\) for the three units, \(\$ 50\) for four units, and \(\$ 80\) for five units. In the form of a table, calculate total revenue, marginal revenue, total cost, and marginal cost for each output level (one to five units). What is the profit-maximizing quantity of output? On one diagram, sketch the total revenue and total cost curves. On another diagram, sketch the marginal revenue and marginal cost curves.

In conclusion, the profit-maximizing quantity of output for the AAA Aquarium Co. is 3 units, where the marginal revenue (\(\$20\)) equals the marginal cost (\(\$20\)). The total revenue, marginal revenue, total cost, and marginal cost calculations for each output level are as follows: - 1 Unit: Total Revenue = \(\$20\), Marginal Revenue = -, Total Cost = \(\$40\), Marginal Cost = -. - 2 Units: Total Revenue = \(\$40\), Marginal Revenue = \(\$20\), Total Cost = \(\$45\), Marginal Cost = \(\$5\). - 3 Units: Total Revenue = \(\$60\), Marginal Revenue = \(\$20\), Total Cost = \(\$55\), Marginal Cost = \(\$10\). - 4 Units: Total Revenue = \(\$80\), Marginal Revenue = \(\$20\), Total Cost = \(\$70\), Marginal Cost = \(\$15\). - 5 Units: Total Revenue = \(\$100\), Marginal Revenue = \(\$20\), Total Cost = \(\$100\), Marginal Cost = \(\$30\). Sketching the total revenue, total cost, marginal revenue, and marginal cost curves can aid in visualizing their relationships.