Question: The largest city in the country of the exhibit has a coat of arms. What is that coat of arms based on?

full_context: Document 1: Coat of arms of Moscow: The coat of arms of Moscow depicts a horseman with a spear in his hand slaying a basilisk and is identified with Saint George and the Dragon. The heraldic emblem of Moscow has been an integral part of the coat of arms of Russia since the 16th century.
Document 2: Moscow: Moscow (/ ˈmɒskoʊ / or / ˈmɒskaʊ /; Russian: Москва́, tr. Moskva, IPA: (mɐˈskva) (listen)) is the capital and most populous city of Russia, with 12.2 million residents within the city limits and 17.1 million within the urban area. Moscow has the status of a Russian federal city.
Document 3: Saint Petersburg: Saint Petersburg (Russian: Санкт - Петербу́рг, tr. Sankt - Peterburg, IPA: (ˈsankt pjɪtjɪrˈburk) (listen)) is Russia's second - largest city after Moscow, with 5 million inhabitants in 2012, part of the Saint Petersburg agglomeration with a population of 6.2 million (2015). An important Russian port on the Baltic Sea, it has a status of a federal subject (a federal city).
Document 4: Moscow Kremlin: The Moscow Kremlin (Russian: Моско́вский Кремль, tr. Moskovskiy Kreml, IPA: (mɐˈskofskjɪj krjemlj)), usually referred to as the Kremlin, is a fortified complex at the heart of Moscow, overlooking the Moskva River to the south, Saint Basil's Cathedral and Red Square to the east, and the Alexander Garden to the west. It is the best known of the kremlins (Russian citadels) and includes five palaces, four cathedrals, and the enclosing Kremlin Wall with Kremlin towers. Also within this complex is the Grand Kremlin Palace that was formerly the tsar's Moscow residence. The complex serves as the official residence of the President of the Russian Federation.
Document 5: General Satellite: May, 19th, 2010London, Great Britain. World premiere of 3 DV channel. GS Group and Valery Gergiev presented joint 3D-project at the press-conference in Barbican-centre, London. General Satellite Corporation announced the launch of its own European 3D TV channel 3DV which will be filled with different content, including the one dedicated to culture and travelling. Considerable part of channel’s programs will be the Mariinsky Theatre programs. Fragments from the Mariinsky Theatre Gala Concert and Giselle ballet staged at the Mariinsky Theatre were presented in 3D during presentation before press-conference.
Document 6: European Russia: European Russia is the western part of Russia that is a part of Eastern Europe. With a population of 110 million people, European Russia has about 77% of Russia's population, but covers less than 25% of Russia's territory. European Russia includes Moscow and Saint Petersburg, the two largest cities in Russia.
Document 7: General Satellite: February, 2nd, 2010 – GS Group announced launching of the first 3D-broadcasting in Russia and Eastern Europe. On April 15, for the first time in Russia the live 3D broadcast was performed by the company (Gala concert in the Mariinsky Theatre). European premiere of the satellite channel with three-dimensional image 3DV was held on May 21 in London.
Document 8: St. Petersburg, Florida: St. Petersburg is a city in Pinellas County, Florida, United States. As of the 2015 census estimate, the population was 257,083, making it the fifth-most populous city in Florida and the largest in the state that is not a county seat (the city of Clearwater is the seat of Pinellas County).
Document 9: Moscow: Moscow is situated on the Moskva River in the Central Federal District of European Russia, making it Europe's most populated inland city. The city is well known for its architecture, particularly its historic buildings such as Saint Basil's Cathedral with its brightly coloured domes. With over 40 percent of its territory covered by greenery, it is one of the greenest capitals and major cities in Europe and the world, having the largest forest in an urban area within its borders -- more than any other major city -- even before its expansion in 2012. The city has served as the capital of a progression of states, from the medieval Grand Duchy of Moscow and the subsequent Tsardom of Russia to the Russian Empire to the Soviet Union and the contemporary Russian Federation.
Document 10: General Satellite: June 17–19, 2010During Petersburg Economic Forum, President of the Russian Federation D.A. Medvedev visited the exhibit of the Commission on modernization and technological development of the economy of Russia, where he watched the demonstration of Corporation’s developments in the field of 3D TV, namely, the first Russian 3D channel – 3DV.
Document 11: High-definition television: In 1958, the Soviet Union developed Тransformator (Russian: Трансформатор, meaning Transformer), the first high-resolution (definition) television system capable of producing an image composed of 1,125 lines of resolution aimed at providing teleconferencing for military command. It was a research project and the system was never deployed by either the military or consumer broadcasting.
Document 12: Flag of Saint Petersburg: The flag of Saint Petersburg, in the Russian Federation, is a red field charged in the centre with the arms of the city, which consists of two silver anchors (a sea anchor, and a river anchor), and a gold scepter.
Document 13: 3D television: Stereoscopic 3D television was demonstrated for the first time on 10 August 1928, by John Logie Baird in his company's premises at 133 Long Acre, London. Baird pioneered a variety of 3D television systems using electro - mechanical and cathode - ray tube techniques. The first 3D TV was produced in 1935, and stereoscopic 3D still cameras for personal use had already become fairly common by the Second World War. Many 3D movies were produced for theatrical release in the US during the 1950s just when television started to become popular. The first such movie was Bwana Devil from United Artists that could be seen all across the US in 1952. One year later, in 1953, came the 3D movie House of Wax which also featured stereophonic sound. Alfred Hitchcock produced his film Dial M for Murder in 3D, but for the purpose of maximizing profits the movie was released in 2D because not all cinemas were able to display 3D films. In 1946 the Soviet Union also developed 3D films, with Robinzon Kruzo being its first full - length 3D movie. People were excited to view the 3D movies, but were put off by their poor quality. Because of this, their popularity declined quickly. There was another attempt in the 1970s and 80s to make 3D movies more mainstream with the releases of Friday the 13th Part III (1982) and Jaws 3 - D (1983). 3D showings became more popular throughout the 2000s, culminating in the success of 3D presentations of Avatar in December 2009 and January 2010.
Document 14: St. Petersburg, Florida: St. Petersburg is the second - largest city in the Tampa Bay Area, after Tampa. Together with Clearwater, these cities comprise the Tampa -- St. Petersburg -- Clearwater Metropolitan Statistical Area, the second - largest in Florida with a population of around 2.8 million. St. Petersburg is located on a peninsula between Tampa Bay and the Gulf of Mexico, and is connected to mainland Florida to the north.
Document 15: Saint George and the Dragon (Uccello): Saint George and the Dragon is a painting by Paolo Uccello dating from around 1470. It is on display in the National Gallery, London, United Kingdom. It was formerly housed in the Palais Lanckoroński in Vienna, belonging to Count Lanckoroński and sold by his son and heir Anton in 1959 through Mr Farago. The first mention of it being there is 1898.
ground_truth: Saint George and the Dragon
sub_queries: where was the exhibit held? Answer: Russia
what city is Russia ’s largest metropolitan area as measured by population Answer: Moscow
coat of arms of Moscow >> based on Answer: Saint George and the Dragon