Final answer:
The electrode for lead V3R should be placed on the right side of the sternum at the fourth intercostal space when performing an EKG on an infant.
Step-by-step explanation:
When performing an EKG on an infant, the electrode for lead V3R should be placed on the right side of the sternum at the fourth intercostal space. In a standard 12-lead ECG, six electrodes are placed on the chest, and four electrodes are placed on the limbs. The placement of the electrode for lead V3R is specific to the right side of the sternum at the fourth intercostal space. This location allows for accurate recording of the electrical signals from the heart.