This is an interesting question, and the answer tells us something important about how planets form, as astronomers believe whether a planet travels clockwise or counterclockwise around its star is ...

In a “normal” electrocardiogram (ECG), the transition of the QRS axis in the precordial leads occurs between leads V 3 and V 4 (i.e., there is a dominant S in V 3 and a dominant R in V 4).