Final answer:
In mass manufacturing, the firm consistently produces the same products, which allows for expanded production over the long term. This production method benefits from economies of scale and technological efficiencies like the assembly line, leading to lower costs over larger outputs.
Step-by-step explanation:
In mass manufacturing, the firm produces the same product(s) over a long period of time. Mass manufacturing allows for producers of goods and services to expand production more easily in the long term over several years, rather than in the short run of a few months. It enables a design that leads to a mechanized work environment focused on producing identical products in every location. This approach to production benefits from economies of scale as technology and efficiency improvements, like the assembly line, lower the average cost of producing each unit of a product over time.
In the long run, it becomes possible to build new factories, hire many new workers, or open new stores, allowing for this expanded production. The long-run average cost curve reflects this, with the downward-sloping economies of scale portion stretching over a larger quantity of output, thus showing that bigger producers can, in many cases, produce at a lower average cost than smaller ones.