Which of the following would be classified as a public good?

If aggregate planned expenditures exceed real GDP, then

A) inventories increase above their planned levels and businesses decrease their production. B) inventories decrease below their planned levels and businesses decrease their production. C) there is no equilibrium level of real GDP. D) unplanned inventory changes equal zero. E) inventories decrease below their planned levels and businesses increase their production.

The four-firm concentration ratio (C4) of a market can be used to help determine whether firms may have market power.

a. true b. false