The correct answers to these open questions are the following.
Although there are no options attached we can say the following.
Why were the city-states in Mesopotamia constantly warring with each other? Because each city-state in Mesopotamia wanted to establish power and control over the other city-states.
How did Sargon finally bring together a unified state?
Sargon was considered to be a good general and a wise ruler of his empire. He appointed governors to help control conquered lands. He established a permanent army. That is why he was capable of uniting the Sumerian city-states with his empire of Akkad.
Why is the adoption of the customs of a conquered people a good strategy for a conquering ruler?
Because this technique allowed people to maintain their way of living, their customs, culture, traditions, and beliefs, and this created sympathy and appreciation for the new ruler.
Sargon the Great was the King of Mesopotamia in ancient Sumeria. Historians consider that he reigned from 2324 to 2279 BC. He was a great King that conquered many territories such as Kish, Asuhr, Cyprus, and Anatolia. He built his city, Akkad, next to the Euphrates River. The clay tablets that recorded the history of Sumer in cuneiform writing refer to many legendary tales of King Sargon.