Question: Which actor from the 1973 American film The World's Greatest Athlete also appeared in "The Mary Tyler Moore Show" and "Roots"?
Context: Nancy Walker (May 10, 1922 – March 25, 1992) was an American actress and comedian of stage, screen, and television.  She was also a film and television director (most notably of "The Mary Tyler Moore Show", on which she also made several guest appearances).  During her five-decade long career, she may be best remembered for her long-running roles as Mildred on "McMillan & Wife" and Ida Morgenstern, who first appeared on several episodes of "The Mary Tyler Moore Show" and later became a prominent recurring character on the spinoff series "Rhoda". "The Mary Tyler Moore Show" opening sequence is an element of the American television series "The Mary Tyler Moore Show".  In 1999, "Entertainment Weekly" picked Mary Richards' hat toss at the end of the sequence as the 1970s' second-greatest television moment.  The theme song, "Love Is All Around", was written and performed by Sonny Curtis. Mary is an American sitcom that aired on CBS from December 11, 1985, to April 8, 1986.  The series stars Mary Tyler Moore in her return to series television after an absence of over six years, during which time she appeared on Broadway in "Whose Life Is It Anyway? " and in the dramatic film "Ordinary People".  After "The Mary Tyler Moore Show", her subsequent ventures into series television on the variety shows "Mary" (1978) and "The Mary Tyler Moore Hour" (1979) had been short-running ratings disasters, and Moore decided to return to the sitcom format which had brought her the greatest television success; the sitcom nonetheless met the same fate as the variety shows. Lou Grant is an American drama series starring Ed Asner in the title role as a newspaper editor that aired on CBS from September 20, 1977 to September 13, 1982.  The series was the third spin-off of the sitcom "The Mary Tyler Moore Show".  "Lou Grant" was created by "The Mary Tyler Moore Show" co-creators James L. Brooks and Allan Burns, along with Gene Reynolds. The World's Greatest Athlete is a 1973 American feature film released by Walt Disney Productions.  It starred John Amos, Roscoe Lee Browne, Tim Conway, Dayle Haddon, and Jan-Michael Vincent.  It is one of the few wide-release Hollywood sports films to look at the world of track and field, as the "World's Greatest Athlete", Nanu, played by Vincent, tries to make history by winning every event at the NCAA Track & Field Championship. Mary Tyler Moore (December 29, 1936 – January 25, 2017) was an American actress, known for her roles in the television sitcoms "The Mary Tyler Moore Show" (1970–1977), in which she starred as Mary Richards, a thirtyish single woman who worked as a local news producer in Minneapolis, and "The Dick Van Dyke Show" (1961–1966), in which she played Laura Petrie, a former dancer turned Westchester homemaker, wife and mother.  Her notable film work includes 1967's "Thoroughly Modern Millie" and 1980's "Ordinary People", in which she played a role that was very different from the television characters she had portrayed, and for which she was nominated for an Academy Award for Best Actress. Mary and Rhoda is a 2000 American made-for-television comedy-drama film starring Mary Tyler Moore and Valerie Harper reprising their roles as Mary Richards and Rhoda Morgenstern from the 1970–77 sitcom "The Mary Tyler Moore Show". John Allen Amos Jr. (born December 27, 1939) is an American actor who is best known for his role as James Evans, Sr. on the CBS television series "Good Times" (1974–76).  Amos' other television work includes roles in "The Mary Tyler Moore Show", the miniseries "Roots", for which he received an Emmy nomination, and a recurring role as Admiral Percy Fitzwallace on "The West Wing".  Amos also played the father of Will Smith's character's girlfriend, Lisa Wilkes, in "The Fresh Prince of Bel-Air", and he had a recurring role on "In the House" with LL Cool J, as Coach Sam Wilson.  Amos played the Father of Tommy Strawn (Thomas Mikal Ford) on the long running sitcom, "Martin", as Sgt. Strawn, and another recurring role on "Two and a Half Men" as Chelsea's dad's new lover, Edward Boynton.  Amos also played Major Grant, the US Special forces officer in "Die Hard 2".  Amos has also appeared on Broadway and in numerous films in a career that spans four decades.  He has received nominations for a Primetime Emmy Award and NAACP Image Award. Phyllis is an American sitcom that aired on CBS from September 8, 1975, to March 13, 1977.  Created by Ed Weinberger and Stan Daniels, it was the second spin-off of "The Mary Tyler Moore Show" (the first being "Rhoda").  The show starred Cloris Leachman as Phyllis Lindstrom, who was previously Mary Richards' landlady on "The Mary Tyler Moore Show". Mary Tyler Moore (December 29, 1936 – January 25, 2017) was an American actress, known for her roles in the television sitcoms "The Mary Tyler Moore Show" (1970–1977), in which she starred as Mary Richards, a single woman working as a local news producer in Minneapolis, and "The Dick Van Dyke Show" (1961–1966), in which she played Laura Petrie, a former dancer turned Westchester homemaker, wife and mother.  Her film work includes 1967's "Thoroughly Modern Millie" and 1980's "Ordinary People", in which she played a role that was very different from the television characters she had portrayed, and for which she was nominated for an Academy Award for Best Actress.
Answer: John Amos