Answer:
The Maya, Inca, and Aztec were all very advanced and used their resources and knowledge to create wonderful understandings and accounts of our world.
The Mayas had amazing knowledge of mathematics and astronomy. At the time, Mayan priests examined the stars and planets with great accuracy, soon learning the movement of the Earth in some regard, and therefore using that knowledge to track the time of a solar year, which they then used to create their calendar. Their results were spot on, with their studies predicting one solar year to be 365.2420 days.
The Incas were amazing engineers. Centralized in Colombia and Chile in South America, they learned how to create complex road systems throughout their empire, even continuing over the rough terrain of the Andes mountains. This was all completed due to the empire's collective labor and centralized economy, which helped the empire prosper further.
The Aztecs were also skilled at engineering and mathematics - using these skills to build large centralized economies, like the Inca, and build large and awe-inspiring temples and pyramids. They also created a calendar, like the Mayas, and proceeded to use it to create a unified military power, and a unique farming system called chinampas.
Step-by-step explanation: