Final answer:
Farmer Brown's neighbors have an easement that allows them access to his potable water well. This easement is a legal agreement defining their property rights to use his land for accessing water.
Step-by-step explanation:
Among the three neighboring properties, Farmer Brown has the only potable water well. All three of his neighbors have a easement allowing them the right to use Farmer Brown's property in order to access the well. An easement is a legal provision that grants the right to use another person's land for a specified purpose, in this case, to access potable water.
The concept of property rights is a key aspect in determining the usage and responsibilities regarding resources and land. In the context of Farmer Brown and his well, the easement forms a legal agreement that defines the property rights of the neighbors to access water. If a dispute arises, the existence of clearly defined property rights and responsibilities can lead to resolution through compensation or negotiation between the parties involved, as indicated by the Coase Theorem.