Final answer:
The two assumptions we set in the study of labor demand by the firm are that the quantity of hours that the average person is willing to work for a given wage does not change significantly in the short run, and there are no substantial short-term changes in factors such as the age structure of the labor force.
Step-by-step explanation:
In the study of labor demand by a firm, we make two primary assumptions. The first assumption is that the quantity of hours that the average person is willing to work for a given wage does not change significantly in the short run. This means that the labor supply curve does not shift much. The second assumption is the ceteris paribus assumption, which means that there are no substantial short-term changes in factors such as the age structure of the labor force, institutions and laws affecting the labor market, or other relevant factors.