In a three-electrode electrocardiogram, the lead II potential is measured between which two points?

1. Three-electrode recordings placed electrodes on the left arm, the right arm and the left leg. 2. Each pair of electrodes forms a lead and measures one component of the depolarization vector. 3. The pair from the right arm to the left leg gives the lead II potential. 4. Lead II is the one most often graphed and is used as an indicator of heart-muscle function. 5. A modern recording uses twelve or more electrodes, but lead II remains the familiar trace. _Source: OpenStax College Physics (CC BY 4.0), Ch 20 "Electric Current, Resistance, and Ohm's Law", section Electrocardiograms_