The presence of diminishing marginal returns to labor leads to decreasing marginal revenue product of labor and a downward-sloping demand for labor curve

What can you learn from the figure below (Figure 13-1 from the text) which depicts the U.S. GNP and its components for the year 2009?

What will be an ideal response?

Long-run market supply curves are downward sloping if

A) firms are identical. B) the number of firms is restricted in the long run. C) input prices fall as the industry expands. D) All of the above.