Question: How many runners compete in the race that Ron Brown won gold in at the 1984 Summer Olympics?

full_context: Document 1: 110 metres hurdles: The 110 metres hurdles, or 110-meter hurdles, is a hurdling track and field event for men. It is included in the athletics programme at the Summer Olympic Games. The female counterpart is the 100 metres hurdles. As part of a racing event, ten hurdles of 1.067 metres (3.5 ft or 42 inches) in height are evenly spaced along a straight course of 110 metres. They are positioned so that they will fall over if bumped into by the runner. Fallen hurdles do not carry a fixed time penalty for the runners, but they have a significant pull-over weight which slows down the run. Like the 100 metres sprint, the 110 metres hurdles begins in the starting blocks.
Document 2: 4 × 400 metres relay: The 4 × 400 metres relay or long relay is an athletics track event in which teams consist of four runners who each complete 400 metres or one lap. It is traditionally the final event of a track meet. At top class events, the first 500 metres is run in lanes. Start lines are thus staggered over a greater distance than in an individual 400 metres race; the runners then typically move to the inside of the track.
Document 3: 4 × 100 metres relay: The 4 × 100 metres relay or sprint relay is an athletics track event run in lanes over one lap of the track with four runners completing 100 metres each. The first runners must begin in the same stagger as for the individual 400 m race. A relay baton is carried by each runner and must be passed within a 20 m changeover box (usually marked by yellow lines) which extends 10 m on either side of each 100 m mark of the race. Another line is marked 10 m farther back, marking the earliest point at which the outgoing runner may begin (giving up to 10 m of acceleration before entering the passing zone).
Document 4: Sprint hurdles at the Olympics: The sprint hurdles at the Summer Olympics have been contested over a variety of distances at the multi-sport event. The men's 110 metres hurdles has been present on the Olympic athletics programme since the first edition in 1896. A men's 200 metres hurdles was also briefly held, from 1900 to 1904. The first women's sprint hurdling event was added to the programme at the 1932 Olympics in the form of the 80 metres hurdles. At the 1972 Games the women's distance was extended to the 100 metres hurdles, which is the current international standard.
Document 5: Ellison Brown: Ellison Myers Brown Sr (September 22, 1914 – August 23, 1975), widely known as Tarzan Brown, and Deerfoot amongst his people, was a two-time winner of the Boston Marathon, in 1936 (2:33:40) and 1939 (2:28:51). A member and direct descendant of the last acknowledged royal family of the Narragansett Indian tribe of Rhode Island, he also participated in the 1936 Summer Olympics in Berlin. He was scheduled to participate in the 1940 Summer Olympics in Helsinki, but these were canceled due to the outbreak of World War II. Tarzan Brown is still one of only two Native Americans to have won the Boston Marathon (the other being Thomas Longboat of the Onondaga Nation from Canada, in 1907) and the only Native American to have more than one victory in Boston. He was inducted into the American Indian Athletic Hall of Fame in 1973.
Document 6: Jim Ryun: James Ronald Ryun (born April 29, 1947) is a former American politician and track and field athlete. He won a silver medal in the men's 1500 metres at the 1968 Summer Olympics, and was the first high school athlete to run a mile in under four minutes. He is the most recent American to hold the world record for the mile run. Ryun later served in the United States House of Representatives from 1996 to 2007, representing Kansas's 2nd congressional district for the Republican Party.
Document 7: 400 metres: The 400 metres, or 400 metre dash, is a common sprinting event in track and field competitions. It has been featured in the athletics programme at the Summer Olympics since 1896 for men and since 1964 for women. On a standard outdoor running track, it is one lap around the track. Runners start in staggered positions and race in separate lanes for the entire course. In many countries, athletes previously competed in the 440 yard dash (402.336 m)—which is a quarter of a mile and was referred to as the 'quarter-mile'—instead of the 400 m (437.445 yards), though this distance is now obsolete. An athlete who competes in the 400 m may still be referred to as 'quarter-miler'; the distance or event might still be called the "quarter."
Document 8: 800 metres: The 800 metres, or 800 meters (US spelling), is a common track running event. It is the shortest common middle-distance running event. The 800 metres is run over two laps of the track (400 metre track) and has been an Olympic event since the first games in 1896. During indoor track season the event is usually run on a 200-metre track, therefore requiring four laps.
Document 9: Ron Brown (American football): Ronald James Brown (born March 31, 1961) is an American former athlete and American football wide receiver, winner of the gold medal in the 4 × 100 metres relay at the 1984 Summer Olympics. He went to Arizona State University.
Document 10: 100 metres hurdles: The 100 metres hurdles, or 100-meter hurdles, is a track and field event run mainly by women (the male counterpart is the 110 metres hurdles). For the race, ten hurdles of a height of 83.8 cm are placed along a straight course of 100 m . The first hurdle is placed after a run-up of 13 metres from the starting line. The next 9 hurdles are set at a distance of 8.5 metres from each other, and the home stretch from the last hurdle to the finish line is 10.5 metres long. The hurdles are set up so that they will fall over if bumped into by the runner, but weighted so this is disadvantageous. Fallen hurdles do not count against runners provided that they do not run into them on purpose. Like the 100 metres sprint, the 100 m hurdles begins with athletes in starting blocks.
Document 11: Lionel James: Lionel "Little Train" James (born May 25, 1962) is a former professional American football player who was selected by the San Diego Chargers in the 5th round of the 1984 NFL Draft. Undersized at 5 ft and 171 lb , James played running back at Auburn University where he shared the backfield with Bo Jackson. James would be a part of the 1983 SEC Champion and Sugar Bowl champion team. He spent his entire 5-year NFL career with the Chargers from 1984-1988. His best year as a pro came during the 1985 season when he set the then-NFL season records for receiving yards by a running back and all-purpose yardage. He also led the AFC in receptions that year.
Document 12: John Brown (offensive lineman): John Brown (born June 26, 1988) is an American football offensive lineman who is currently a free agent. He played college football at University of Florida, Northwest Mississippi Community College and Valdosta State University and attended Lakeland High School in Lakeland, Florida. He has also been a member of the Orlando Predators.
Document 13: Wendy Brown (heptathlete): Wendy Renee Brown (born January 28, 1966) is a retired heptathlete and triple jumper from the United States. She competed in the heptathlon at the 1988 Summer Olympics in Seoul, South Korea, finishing in 18th place behind teammate Jackie Joyner Kersee's still current world record. As the event was in transition to become an official event, she set the world record in the women's triple jump twice in the mid-1980s. Because this was before the event was declared official, neither of those records were officially ratified. Brown went to the University of Southern California where she won the 1986 NCAA Indoor Championship in the Triple Jump and later winning 1988 NCAA Championship in the Heptathlon. She is still the school record holder in the Triple Jump and Heptathlon, as well as being ranked second in Long Jump and High Jump. She's even ranked 5th in the Javelin throw.
Document 14: Michael &quot;Ron&quot; Brown: Michael (Ron) Brown (born February 13, 1967) is a former American football linebacker who played in the National Football League from 1987-1989 for the San Diego Chargers and then traded to the Los Angeles Raiders. Brown forsook what might have been a promising track career to play football. While at High School in 1982, he had the seventh-fastest prep high hurdles time in the country, 13.82 seconds.
Document 15: Tom Brown (guard): Tom Brown (born December 5, 1936) is a former professional Canadian football player, and a former outstanding American college football player. He played collegiately at the University of Minnesota, and won the Outland Trophy in 1960 as the nation's best lineman. He played professional football with the BC Lions of the Canadian Football League, and was made a member of the Canadian Football Hall of Fame in 1984. Brown was inducted into College Football Hall of Fame in 2003.
ground_truth: four