Answer the following question given this paragraph: 

In general, for an electric charge to move from one position to another, there must be a difference in electric potential energy between the two positions. The difference in electric potential energy is called potential difference, or voltage . Voltage is measured in an SI unit called the volt (V). For example, the terminals of the car battery in Figure below have a potential difference of 12 volts. This difference in voltage results in a spontaneous flow of charges, or electric current.


Q: The difference in electric potential energy which allows for an electric charge to move from one position to another is measured by what si unit?


A:
volt