Answer:
For an empire to grow, one state has to take control of other states or groups of people. To better understand these processes, historians can compare specific empires against one another.
By comparing different empires, historians see that the process of growth had some similarities and some differences across empires. The Achaemenid Persian Empire under Cyrus the Great grew substantially in less than 30 years and reached its greatest extent within 75 years. The Roman Republic was founded in the sixth century BCE, but the Roman Empire didn’t reach its greatest extent until 117 CE.
Explanation:
