The immigration rates of the 20th century returned to the high rates of the 19th century

Assuming the existence of economies of scale, if a firm finds that it can reduce its unit cost by decreasing its scale of production, it means that

A) it has too much production capacity relative to its demand. B) it should try to produce less. C) the law of diminishing returns has not taken effect. D) it has too much fixed overhead relative to its variable cost.

Behavioral assumptions

a. make economic models more complex than if these assumptions were removed b. pertain only to consumers c. hold all other things constant d. are ways to test a hypothesis e. describe how individuals are expected to behave