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what is the name of the highest mountain in south america
Aconcagua is highest mountain in South America.
how high is the aconcagua
At 22,837 feet, not only is it the highest mountain in South America, it is the tallest in all of the Americas, as well as the Southern and Western Hemispheres.

Question: what is the tallest in the world
Self-contained rewrite: what is the tallest mountain worldwide