After the emergence of which empire, the Akkad came to designate the area between Nippur and Sippar?
Akkadian Empire: The Akkadian Empire was the first ancient Semitic-speaking empire of Mesopotamia, centered in the city of Akkad and its surrounding region, also called Akkad in ancient Mesopotamia in the Bible. Akkad (region): Akkad is the historical name of a region in northern Mesopotamia around the city of Akkad, probably near the confluence of the Diyala with the Tigris. Akkad (region):  After the emergence of the Akkadian Empire, Akkad came to designate the area between Nippur and Sippar.
Akkadian Empire