___________ is a tendency or a disposition to expect the best outcome or to think hopefully about a situation

The explicit cost of production is also called

A) accounting cost. B) overhead cost. C) direct cost. D) variable cost.

Long-run market supply curves are upward 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.