Final answer:
Between 750 CE and 1000 CE, the powerful empires were the Abbasid Caliphate, the Fatimid Caliphate, and the Songhai Empire, known for their cultural, academic contributions, and significant influence in their regions.
Step-by-step explanation:
The three powerful empires that emerged between 750 CE and 1000 CE were the Abbasid Caliphate, the Fatimid Caliphate, and the Songhai Empire. The Abbasid Caliphate, with its capital in Baghdad, was a major center for science, philosophy, medicine, and education. The Fatimid Caliphate, which originated in North Africa and eventually ruled parts of the Mediterranean, was known for its significant cultural and academic contributions. Lastly, the Songhai Empire was one of the largest empires in African history and was particularly influential in the West African region, known for its trade and wealth.