Refer to the accompanying graph. If this firm is a price taker, then when the price of each unit of output is $30, this firm's total revenue at its profit-maximizing level of output is ________.

During a deflationary period,

A) the price level rises. B) the nominal interest rate does not change. C) the nominal interest rate is less than the real interest rate. D) the real interest rate is less than the nominal interest rate.

If you wanted to compare the quantity of output of a country across time periods, which of the following would you use?

a. the consumer price index b. nominal GDP c. the GDP deflator d. real GDP