Final answer:
The dotted line in the graph of units produced against total cost typically represents the total cost curve which includes both fixed and variable costs. Fixed costs form the vertical intercept of the curve and are constant, while variable costs vary with production and add to the upward slope of the curve.
Step-by-step explanation:
In the graph that depicts the relationship between units produced and total cost, the dotted line usually represents the total cost that changes with the level of production, inclusive of both fixed costs and variable costs. Fixed costs represent the vertical intercept of the total cost curve; these are costs that a company incurs even when there is no production, meaning there are no variable costs at that point. As production increases, variable costs are added to fixed costs, resulting in an upward-sloping total cost curve. This is because variable costs vary with production levels, whereas fixed costs remain constant no matter the quantity of output produced.
It's important to note that total cost and average cost are not graphed together because they represent different metrics. Total cost measures the total dollars spent on production, while average cost measures the cost per unit of output. Therefore, since they are measured in different units, they are depicted on separate graphs for clarity and accurate representation.