Final answer:
In an ECG, the normal axis is in the right lower quadrant, between 0 to +90 degrees. Lead I and aVF both move in a positive direction within this normal range.
Step-by-step explanation:
In a normal electrocardiogram (ECG or EKG), the mean electrical axis (MEA) of the heart is located within the normal axis, which typically resides in the right lower quadrant, specifically between 0° to +90°. Lead I records the voltage between the right and left arms and represents horizontal electrical activity, while Lead aVF records the voltage between the left leg and a midpoint of the right and left arms, representing vertical electrical activity. When considering the MEA's direction, Lead I should be moving in a positive direction, while aVF also moves in a positive direction within the normal axis range.