Final answer:
An easement in gross allows an electric company the rights to install and maintain electric power lines for the purpose of electrical transmission. It grants these rights without benefitting a specific piece of land.
Step-by-step explanation:
The type of easement that gives an electric company the authority to install and maintain electric power lines is known as an easement in gross. This type of easement does not benefit any particular piece of land, but instead grants rights to a specific entity or person regardless of land ownership. This allows the electric company to distribute voltage from the electrical power plant for transmission along power lines, thereby providing electricity to homes and businesses.