Arrange the following steps in the correct sequence to understand how a firm can maximize profit through marginal costs and total revenue: A) Analyze how total revenue changes with price adjustments, B) Calculate the marginal cost of producing an additional unit, C) Determine the optimal output level where marginal cost equals marginal revenue, D) Assess total costs to ensure they are less than total revenue.

To maximize profit, a firm should first analyze how total revenue changes with price adjustments, which helps understand how much money is made from selling products. Next, the firm calculates the marginal cost of producing an additional unit to see how much it costs to make one more item. After that, it determines the optimal output level where marginal cost equals marginal revenue, as this is the point where profit is maximized. Finally, the firm assesses total costs to ensure they are less than total revenue, confirming that it is indeed making a profit. For example, if a company finds that producing one more gadget costs $5 and sells for $10, it shows profit potential at that output level.