Comparing marginal revenue to marginal cost (i) reveals the contribution of the last unit of production to total profit. (ii) is helpful in making profit-maximizing production decisions. (iii) tells a firm whether its fixed costs are too high

The OPEC oil shocks in 1973-1974 are an example of:

A) favorable supply shock, shifting the short-run aggregate supply curve rightward. B) favorable supply shock, shifting the short-run aggregate supply curve leftward. C) adverse supply shock, shifting the short-run aggregate supply curve rightward. D) adverse supply shock, shifting the short-run aggregate supply curve leftward.

Economists are concerned with an individual's

A) needs because needs represent the most important goods to an individual. B) needs because economists define needs to be the goods people need to survive. C) wants because, unlike needs, wants lead to shortages in the economy. D) wants because the existence of wants leads to scarcity.