Price cannot fall so low that some sellers choose to supply a quantity of zero

Increasing marginal returns always occurs when the

A) marginal product of an additional worker exceeds the marginal product of the previous worker. B) average product of an additional worker exceeds the average product of the previous worker. C) marginal product of an additional worker is less than the marginal product of the previous worker. D) average product of an additional worker is less than the average product of the previous worker. E) marginal product of an additional worker exceeds the average product of the previous worker.

An increase in the desire to save by households will cause

A) a reduction in output. B) a reduction in investment. C) an increase in output. D) no change in investment and no change in output.