1. What did the Maya, Aztec, and Inca invent?

Two thousand years ago, the ancient Maya developed one of the most advanced civilizations in the Americas. They developed a written language of hieroglyphs and invented the mathematical concept of zero. With their expertise in astronomy and mathematics, the Maya developed a complex and accurate calendar system.

The Aztecs were famous for their agriculture, cultivating all available land, introducing irrigation, draining swamps, and creating artificial islands in the lakes. They developed a form of hieroglyphic writing, a complex calendar system, and built famous pyramids and temples.

Incas also invented a flute, a drum, the famous Inca panpipe (a collection of hollow tubes of various lengths stuck together), terrace farming, freeze dried foods, aqueducts, strange and scary art, a central government, a unified language, woven colorful textiles, gold and silver jewelry and statues

(hope it helps.. random but i'm happy to answer as i am a mayan!)