Question: Dennis Anderson attended a college that closed in what year?

Context paragraphs:
Grave Digger (truck): Grave Digger is a monster truck racing team in the Feld Entertainment Monster Jam series.  There are nine Grave Diggers being driven by different drivers to allow them to make appearances at more events, but their flagship driver is creator Dennis Anderson.  Dennis Anderson is the head of the Grave Digger department team.  He is in charge of the training of the younger drivers and the fleet of trucks.  Grave Digger is considered to be one of the most influential and iconic monster trucks of all time.

Dennis Anderson (politician): Dennis Anderson (born August 16, 1949) is a former provincial-level politician from Alberta, Canada.  At seventeen, Dennis attended Rochdale College in Toronto and started the Rochdale Drug Crisis centre.  He has continued to advocate for mental health ever since.

Fraser Anderson: Fraser Anderson attended The Church College of New Zealand.  He is a member of The Church of Jesus Christ of Latter-day Saints and served for two years as a missionary in Olongapo in the Philippines.

Nahshon Dion Anderson: Anderson was born in Los Angeles County in the suburb of Altadena and raised as a Jehovah's Witness.  Anderson's family resided in Pasadena since the 1950s.  Anderson attended John Marshall Fundamental Junior High School with Actress Lark Vorhees and Tamala Jones as well as Actors Jaleel White and Jaharay Benett.  As a member of Ms. Smiths drama club, Anderson was invited to view live TV show tapings of various sitcoms at Sony Studios in Culver City, mainly Family Matters.

Shandon Anderson: Shandon Rodriguez Anderson (born December 31, 1973) is an American retired professional basketball player who played in the National Basketball Association (NBA) from 1996 to 2006.  Growing up in Atlanta, Anderson attended the University of Georgia and played for four teams during his ten-year NBA career after being drafted by the Utah Jazz in 1996: the Jazz, Houston Rockets, New York Knicks, and Miami Heat.  He played the shooting guard and small forward positions.

Walter Anderson (baseball): Walter Carl Anderson (September 25, 1897 – January 6, 1990), also known as "Lefty" Anderson, was a professional baseball player whose playing career spanned five season, including parts of two in Major League Baseball with the Philadelphia Athletics in 1917 and 1919.  Anderson compiled a major league record of 1–0 with a 3.25 earned run average (ERA) and 20 strikeouts in 17 games, two starts.  He also played in the minor leagues with the Class-B Fort Worth Panthers, the Double-A Louisville Colonels and the Class-B Rockford Rox.  Before his professional career, Anderson attended Western Michigan University.  Anderson also served in World War I.  Anderson batted and threw left-handed.

E. Ruth Anderson: Elsie Ruth Anderson (never married; 23 June 1907 Newport, Rhode Island – 24 November 1989 Boston, Massachusetts) was an American musicologist, meteorologist, and editor.  Anderson attended the New England Conservatory of Music from 1924 to 1931, again in 1934, and again from 1940 to 1941.  On June, 23, 1931, Anderson received a Diploma in Orchestra with a concentration in Violin from the New England Conservatory of Music.

Bob Anderson (wrestler): Bob Anderson (born 1943) is an American wrestler and coach.  Anderson was born in 1943 in Oakland, California and is from Redondo Beach, California.  He attended South High School (Torrance, California) where he placed 3rd his junior year, and finishing as a state champ his senior year.  He won the 1968 Western Regional Olympic Trials and went on to win the 1968 Olympic trials.  Anderson attended El Camino College where he won state as a sophomore had a record-breaking 1 loss the whole season.  Anderson ended up transferring to Adams State College, he then became a 2 time NAIA champion, and was Rocky Mountain Champion.  Anderson was an NCAA All American.  Anderson competed and won in the 1968 Olympic Trials in Greco Roman style and was alternate on the 1968 Olympic Team.  He also wrestled freestyle.  He wrestled Greco Roman in the 1971 Pan American Games, and in Sambo sytyle at the 1979 US Sambo World Team Championships.  He coached and competed in the Pan American games in 1978, earning an individual and a coaching championship.  Anderson coached 2 national teams in Sambo, placing 2nd and 3rd.  In 1996 Anderson had trained Rolls Gracie, whom he would teach techniques like the Americana Arm Bar.  He was a 1996 US Olympic Team Wrestling Coach.  In 2003, he became the World Masters Wrestling Champion at 211 lbs.  Anderson has also trained Rulon Gardner, Dan Henderson, Heath Sims, and Randy Couture.

Rochdale College: Opened in 1968, Rochdale College was an experiment in student-run alternative education and co-operative living in Toronto, Ontario, Canada.  It provided space for 840 residents in a co-operative living space.  It was also a free university where students and teachers would live together and share knowledge.  The project ultimately failed when it could not cover its financing and neighbours complained that it had become a haven for drugs and crime.  It was closed in 1975.

Courtney Anderson: Courtney Jerome Anderson (born November 19, 1980) is a former American football tight end.  Born in Greenville, Texas, Anderson attended high school in Richmond, California and played college football at Contra Costa College and San Jose State University.  He was drafted by the Oakland Raiders in the seventh round of the 2004 NFL Draft and spent three seasons with that team.  Later, he was a member of the Miami Dolphins, Detroit Lions, Atlanta Falcons, Buffalo Bills and Houston Texans.  He is currently a firefighter for the community of Milpitas, CA.

Supporting paragraphs: Dennis Anderson (politician) Rochdale College
Answer: 1975