Question: Which battle resulted as a conflict between the United States Army and the Sioux and involved a Hunkpapa Lakota holy man who was killed by Indian agency police on the Standing Rock Indian Reservation?
Sentence (from "Crow Indian Reservation"): It has a land area of 3,593.56 sq mi (9,307.27 km²) and a total area of 3,606.54 sq mi (9,340.89 km²), making it either the fifth or sixth largest reservation in the country.
Relevant evidence: No