_________ says that the marginal product of a factor input initially rises with its employment level. But after reaching a certain level of employment, it starts falling.
3. If the ___________ firm has zero costs or only has fixed cost, the quantity supplied in equilibrium is given by the point where the marginal revenue is zero.
5. If the ___________ firm has zero costs or only has fixed cost, the quantity supplied in equilibrium is given by the point where the average revenue is zero.
8. Calculate a country's GDP if for the year, consumer spending is $400 million, government spending is $150 million, investment by businesses is $80 million, exports are $35 million and imports are $40 million.