He created one writing system and standardized measurements. He made a national army and navy and built the Great Wall. He collected all the philosophical writings into a library. He sent teams of mapmakers out to chart the country.
You are near the equator, which is part of the tropical zone
Slave rebellion is the correct answer
From research I think the theory is ‘Island Rule’ but what I know is that he realized that on isolated islands the sizes of animals would differ from their mainland relatives. This is because of the scarcity of foods on islands or the lack of predators