NEW YORK — SELECTIONS for the 1991 Whitney Biennial Film/Video Exhibition were chosen by John G. Hanhardt, the Whitney Museum's curator of film and video.Following the pattern established by past editions of the show, this year's program was shown first at the Whitney and is now beginning an extensive tour, expected to reach at least three dozen venues during the next two years. The tour is sponsored by the American Federation of Arts, a New York-based organization that has been the Whitney's regular partner in this enterprise since 1979. Engagements that have already been confirmed include: * Cleveland: Cleveland Cinematheque, Sept. 12-25 (film selections only) * Miami: Alliance for Media Arts, Oct. 1-14 (film selections only) * Keene, N.H.: Thorne Art Gallery, Keene State College, Oct. 17-31 (film and video selections) * Lincoln, Mass.: DeCordova Museum, November (video selections only) * Ithaca, N.Y.: Cornell Cinema, date to be announced (film and video selections) Certain films shown during the exhibition's original run at the Whitney are not included in the touring program, for contractual reasons, or are available only to institutions with the capability for 35-mm projection. "Paris Is Burning," the acclaimed Jennie Livingston documentary on the "voguing" fad among minority teenagers and gays, is not included in the tour, but has recently gone into widespread theatrical release. Meredith Monk's lyrical "Book of Days" and Pat O'Neill's ambitious "Water and Power " are limited to 35-mm exhibition. All other films are in the widely accessible 16-mm format, which is standard for nontheatrical films and documentaries. The film and video programs are available for booking either separately or together. Participating artists not mentioned here include filmmaker Yvonne Rainer and videomakers Francesc Torres, Gary Hill, Rea Tajiri, Juan Downey, Lawrence Andrews, Ericka Beckman, Mike Kelley, Janice Tanaka, Antonio Muntadas, Tom Kalin, Tony Cokes, Donald Trammel, Hans Breder, and Victor Masayesva, Jr.