Question

describing thermal equilibrium
what occurs at thermal equilibrium?
heat flows from the higher - temperature substance to the lower - temperature substance.
heat flows from the lower - temperature substance to the higher - temperature substance.
heat does not flow because both substances are at the same temperature.

Explanation:

Thermal equilibrium is reached when two substances in thermal contact have the same temperature. At this point, there is no net heat - transfer between them as the rate of heat flow from one to the other is equal to the rate of heat flow in the opposite direction.

Answer:

Heat does not flow because both substances are at the same temperature.