Final answer:
The fall of the Inca and Persian empires were both weakened by the death of rulers and recent civil wars.
Step-by-step explanation:
Both the fall of the Inca and Persian empires had in common that they were weakened by the death of rulers and recent civil wars. In the case of the Inca Empire, the death of the emperor Huayna Capac led to a succession crisis and a civil war between his sons, which ultimately weakened the empire. Similarly, the Achaemenid Persian Empire faced internal strife and power struggles after the death of Darius III, which provided an opportunity for Alexander the Great to conquer the empire.
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