I want to know the answer to the following question:
During what periods did the Sumerican city-states rise to power?
All the background I'm provided with is that "Sumerian written history reaches back to the 27th century BC and before, but the historical record remains obscure until the Early Dynastic III period, c. the 23rd century BC, when a now deciphered syllabary writing system was developed, which has allowed archaeologists to read contemporary records and inscriptions.". Is that enough to answer the question?
Answer: no