Final answer:
The Amazon River is the longest river in South America, while the Andes Mountains are the continent's major mountain chain. The Amazon covers vast areas with its tributaries, and the Andes are the longest and highest mountain range in the Americas.
Step-by-step explanation:
Longest River and Major Mountain Chain in South America
The longest and most extensive river in South America is the Amazon River, known for its vast length of over 2,000 miles and impressive discharge, carrying about one-fifth of all river water in the world. The Amazon River, with its numerous tributaries, covers 40 percent of South America. Flowing parallel to the equator, it competes with the Nile for being the longest river in the world.
The major mountain chain in South America is the Andes Mountains. Spanning approximately 5,000 miles along the western part of the continent, the Andes Mountains are the longest mountain chain on Earth and the highest in the Americas, containing peaks surpassing 20,000 feet.