Question: Chisholm Trail Casino is a casino that opened in Duncan, Oklahoma in October of which year, the casino is 70 miles south of Norman, a city in the U.S. state of Oklahoma 20 mi south of downtown Oklahoma City?
Sentence (from "Norman, Oklahoma"): Norman is a city in the U.S. state of Oklahoma 20 mi south of downtown Oklahoma City in its metropolitan area.
Relevant evidence: Yes