Major macroeconomic issues include differences across countries in all of the following EXCEPT:

In the above figure, at a price of $4 per unit, a profit-maximizing perfectly competitive firm will

A) shut down because its total revenue is less than its variable costs. B) incur an economic loss. C) produce 5 units. D) Both answers A and B are correct.

By adding internal costs to external costs, we determine the total

A) private cost. B) social cost. C) psychological cost. D) marginal cost.