An economy could produce above its potential GDP for a short period of time by a. reducing the size of the labor force. b. adding extra shifts of work, such as overtime or night shifts. c. increasing the money supply. d. increasing the price of final goods and services.

To determine which option allows an economy to produce above its potential GDP for a short period of time, let's analyze each option: a. **Reducing the size of the labor force**: This would likely decrease production capacity, not increase it. Therefore, this option is not correct. b. **Adding extra shifts of work, such as overtime or night shifts**: This option allows existing resources (labor) to be utilized more intensively, which can temporarily increase production above potential GDP. This is a valid option. c. **Increasing the money supply**: While increasing the money supply can stimulate demand, it does not directly increase the economy's productive capacity. It may lead to inflation rather than an increase in output above potential GDP. Thus, this option is not correct. d. **Increasing the price of final goods and services**: This does not directly affect the economy's ability to produce more; it may simply reflect inflationary pressures. Therefore, this option is not correct. Based on this analysis, the correct answer is: **b. adding extra shifts of work, such as overtime or night shifts.**