Question: Reima Juhani Karppinen won a silver medal at what event that was held from August 30 to September 6 in 1981, at Oberschleibheim, outside Munich, Germany?
Context: Akiko Iwamoto (岩本 亜希子 , Iwamoto Akiko , born September 25, 1978) is a Japanese rower.  She was born in Nagano Prefecture.  She competed in the Women's lightweight double sculls at the 2012 Summer Olympics, reaching the semi-finals with her teammate Atsumi Fukumoto and ranking 12th overall.  She competed in the same event at the 2000, 2004 and 2008 Summer Olympics, finishing 9th, 14th and 13th respectively.  She won a silver medal in the Women's double sculls at the 2002 Asian Games.  She also won a silver medal in the Women's lightweight double sculls at the 2006 Asian Games, and another silver medal in the Women's lightweight double sculls at the 2010 Asian Games. Song competed for South Korea in the 1956 Summer Olympics held in Melbourne, Australia.  In the bantamweight boxing event, he captured the silver medal.  His silver medal was South Korea's first silver medal at the Olympic Games. Vivian Jepkemoi Cheruiyot (born 11 September 1983) is a Kenyan long-distance runner who specialises in track and cross country running, olympic champion in 5000 metres event.  She represented Kenya at the 2000 Summer Olympics, the 2008 Summer Olympics, the 2012 Summer Olympics and the 2016 Summer Olympics, winning a silver medal at the 5000 m and bronze medal at the 10000 m at the 2012 Olympics, silver medal at the 10000 m and gold medal at the 5000 m at the 2016 Olympics, setting the new Olympic record in 5000 m event.  Cheruiyot won a silver medal in the 5000 metres at the 2007 World Championships in Athletics and became the world champion in the event at the 2009 edition, repeating this achievement at the 2011 World Championships, where she doubled up by winning the 10000 m. Paul John Lake, OAM (born 6 June 1970) is an Australian Paralympic cyclist.  He was born in Melbourne.  He won a silver medal at the 1996 Atlanta Games in the Mixed Omnium LC2 event.  At the 2000 Sydney Games, he won a gold medal in the Mixed Team Olympic Sprint LC1–3 event, for which he received a Medal of the Order of Australia, a silver medal in the Mixed Individual Pursuit LC2 event, and a bronze medal in the Mixed 1 km Time Trial LC2 event.  He was an Australian Institute of Sport scholarship holder in 1995 and 1997. Annelie Ehrhardt, (née Jahns on 18 June 1950) is a retired German hurdler.  She won the gold medal in the inaugural 100 metre hurdles event at the 1972 Summer Olympics held in Munich, Germany, setting a new world record, and becoming the first East German Olympic Champion in this event.  She also won a silver medal at the 1971 European Championships and a gold medal at the 1974 European Championships in a new championship record of 12.66 seconds. John Lindsay, OAM (born 29 January 1970) is an Australian Paralympic athlete from Melbourne.  He competed in the 1988 Seoul games in distances ranging from 100 m to 800 m, but did not win any medals.  At the 1992 Barcelona Games, he won a gold medal in the Men's 200 m TW3 event, for which he received a Medal of the Order of Australia, a silver medal in the Men's 100 m TW3 event and a bronze medal in the Men's 400 m TW3 event.  That year, he had a Victorian Institute of Sport scholarship.  He was also working as a fitness instructor in 1992, held world records in the 100 m and 200 m events, and was ranked 6th in the world in the 400 m.  He won a gold medal in the men's athletics 100 m T52 event at the 1996 Summer Paralympics with a time of 15.22, a silver medal in the 200 m T52 event with a time of 27.38, and a bronze medal in the 400 m T52 event with a time of 52.93.  At the 2000 Sydney Games, he won a gold medal in the Men's 100 m T53 event, a silver medal as part of the Men's 4x100 m Relay T54 team, and a bronze medal in the Men's 200 m T53 event; he was also part of the Men's 4x400 m Relay T54 team, which was the only one to qualify in its heat, but it did not make it to the finals.  At the 2004 Athens Games, he came seventh in the first round of the Men's 100 m T53 event and sixth in the third round of the Men's 200 m T53 event.  He was an Australian Institute of Sport scholarship holder in 1995 and 2000. The 1981 World Rowing Championships were World Rowing Championships that were held from 30 August to 6 September 1981 at Oberschleißheim outside Munich, Germany. Achim Hill (April 1, 1935 – August 4, 2015) was a German rower who competed for the Unified Team of Germany in the 1960 Summer Olympics and in the 1964 Summer Olympics and for East Germany in the 1968 Summer Olympics.  He was born in Köpenick.  In 1960 he won the silver medal in the single sculls event.  Four years later he won his second silver medal in the 1964 single sculls competition.  At the 1968 Games he represented East Germany and finished fifth in the single sculls contest. Reima Valdemar Virtanen (born November 5, 1947 in Kemi, Finnish Lapland) is a former boxer from Finland, who won the silver medal in the middleweight division (– 75 kg) at the 1972 Summer Olympics in Munich.  He was nicknamed "Kila" and "Rema" during his career.  In the final Virtanen was knocked out in 2:17 of the first round by Vyacheslav Lemechev of the Soviet Union. Reima Juhani Karppinen (born 27 January 1958) is a retired Finnish rower who specialized in the double sculls.  In this event, he won a silver medal at the 1981 World Rowing Championships, together with his legendary brother Pertti.  He competed at the 1984, 1988 and 1992 Summer Olympics, with other partners, and finished in 8th, 12th and 13th place, respectively.
Answer: The 1981 World Rowing Championships