What is one method used by the Incas to unify their large empire?(1 point) Responses They built restaurants in the middle of the city so everyone could eat together. They built restaurants in the middle of the city so everyone could eat together. They created a post office so people could mail letters and stay in touch. They created a post office so people could mail letters and stay in touch. They developed an extensive road and bridge system throughout the empire to make trade and travel easier. They developed an extensive road and bridge system throughout the empire to make trade and travel easier. They were not able to unify their large empire. They were not able to unify their large empire.