I would say that there aren't really any absolute standards for truth and justice. The reason for this is that considering we're only one species that has evolved out of apes, it is really hard to say whether the way we perceive reality and discover things through science can be thought as an absolute standard for truth. From this perspective it's even harder to find an absolute standard for justice.
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I believe the answer is 4. During the reign of Askia Muhammad, the Songhai empire reached its greatest size.
Askia Muhammad was an emperor, military commander, and political reformer of the Songhai Empire in the 15th century. His rule resulted in trade with Europe and Asia, building of lots of schools, and spread of Islam through his empire.
Hope this helps! Please let me know if I'm wrong :)
