An asset that will allow people to transfer purchasing power from one period to the next is known as a:（）

单项选择题In the short run, the impact of an increase in the money supply on the price level and real output will be: Price level Real output（） ①A. Increase Increase ②B. Increase No change ③C. No change Increase

A. ①
B. ②
C. ③

单项选择题The idea behind the Laffer curve is that increases in tax rates do not increase tax revenues proportionately because they decrease the:（）

A. demand for labor.
B. supply of labor.
C. productivity of labor.