Final answer:
Potassium (K+) returns to the outside of the cell through leakage via potassium channels due to the concentration gradient established by the active transport of the Na+/K+ pump.
Step-by-step explanation:
In the Na+/K+ pump, some K+ returns to the outside by leakage through potassium channels that are often open, allowing K+ to flow down its concentration gradient. The sodium-potassium pump, which actively transports K+ ions into the cell and Na+ ions out, creates a high concentration of K+ inside the cell and a high concentration of Na+ outside the cell. As a result of this concentration gradient, K+ can exit the cell passively through these channels, which helps to maintain the electrochemical gradient required for various cellular functions, including the generation of electrical signals in neurons.