Question: In what City was the Realpha car based on?

full_context: Document 1: Alfa Romeo RM: Alfa Romeo RM was produced between 1923–1925, it was based on RL model. Car was introduced first time in 1923 Paris Motor Show and total production was around 500 cars. RM had 2.0 L straight-4 engine, which produced between 40 bhp to 48 bhp . As most of Alfa Romeo cars this was also used in racing purpose.
Document 2: Ferrari: Ferrari N.V. (] ) is an Italian sports car manufacturer based in Maranello. Founded by Enzo Ferrari in 1939 out of Alfa Romeo's race division as "Auto Avio Costruzioni", the company built its first car in 1940. However the company's inception as an auto manufacturer is usually recognized in 1947, when the first Ferrari-badged car was completed.
Document 3: Nota: Nota Sports and Racing Cars is an automobile manufacturer in Australia. The company was founded by Guy Buckingham in 1952. He was an aircraft engineer and used his expertise to build triangulated spaceframed sportscars. Possibly Australia's first space-framed cars. In 1958 the company built a series of all-enveloping aluminium streamlined sports cars. First called "Streamliners", and later called "Mazengarbs". Up to 1960 eleven of those were made. In the late 1950s the company produced Formula Junior cars in both front and midengined formats. Nota also made a series of specialist monoposto racing cars for the track and hill climbing events. In 1963 the company made a series of Mini powered sports cars. In 1964 they started production of the Nota Sapphire an alloy bodied sports and coupe designs with Ford Fiat and Coventry Climax engines. In 1965 Nota started producing Formula Vee cars for Warrick Farm race track making 34 in the first year. In the 1960s the company formulised their "Sportsman", a Lotus 7 look alike, which they still build today and are now building in a midengined version for the modern day transverse engines which the major car manufacturers produce. In 1968 came the Nota Fang Chris Buckinghams first real design, a midengined sports car using a Cooper S engine power plant behind the driver but in front of the rear wheels, their most successful model with over 100 being made. Later the Fang was equipped with Lancia engines, then Toyota engines, finally being fitted with Toyota's V6 Quad cam supercharged engines with over 400BHP. In 1973 Nota started with their Marauder range of cars using the same mechanicals as the Nota Fang. At the same time they were making the Nota Levanti front engine twin cam coupe. In 1975 the supply of Leyland 1275 GT engines started to run out so Nota contacted FIAT and both Marauders and Fangs were made with the 2-litre twin cam FIAT/Lancia engine.
Document 4: Realpha: The Realpha, also known as RE, was a Rhodesian Formula One racing car. The car was built by Ray Reed at his base in Gwelo, and was structurally based on a Cooper. Like many South African home-built Formula One cars of the time, it was fitted with an Alfa Romeo Giulietta engine.
Document 5: Caterham Cars: Caterham Cars is a British manufacturer of specialist lightweight sports cars established in Caterham, Surrey, with their headquarters in Crawley, Sussex. Their current model, the Caterham 7 (or Seven), originally launched in 1973, is a direct evolution of the Series 3 Lotus Seven designed by Colin Chapman. In the 1990s the company made the Caterham 21, a two-seater soft top alternative to the MGF and Lotus Elise, (which both sold many more units). A track-only car, the SP/300.R, a joint project with Lola was released for customer testing in 2010 and was scheduled for release in 2013. On 27 April 2011, Team Lotus owner Tony Fernandes announced that he had purchased Caterham.
Document 6: BRM P139: The BRM P139 was a Formula One racing car designed by Alec Osborne, based on the original P126/133/138 design by Len Terry, which raced during the and seasons. It was powered by a 3.0-litre V12 engine. The car was uncompetitive, which resulted in team boss Tony Rudd being asked to resign, with his position being taken over by Tony Southgate, Tim Parnell and Aubrey Woods. After the team did not attend the French Grand Prix, a redesigned P139 appeared at the British Grand Prix, with a roomier, more bulbous cockpit and additional strengthening, giving the P139 a cylindrical appearance. The revised car was barely an improvement on the original P139, and was replaced by the P153 for the 1970 season. The P139 made one final appearance, at the 1970 South African Grand Prix, driven by George Eaton, who was effectively paying for his drive, and thus did not receive a 'works' P153.
Document 7: Romano WE84: The Romano WE84 is an Australian designed and built, mid-engined closed top racing car built to CAMS Group A Sports Car specifications. The car began its life as the Kaditcha K583 when it first appeared in the 1983 Australian Sports Car Championship and was built by the Queensland based Kaditcha owner and former McLaren engineer Barry Lock after he was approached by Brisbane accountant, property developer, timber mill owner and former speedway racer Bap Romano in 1981 with the idea of building a Le Mans type coupe. When the car first appeared in 1983, it was the first closed top Sports Car seen in Australia and looked like an FIA Group C Sports Car (such as the Porsche 956) rather than the open cockpit Can-Am style cars of previous years. This led to the false belief that it was built to the Group C regulations
Document 8: Alvis Car and Engineering Company: Alvis Car and Engineering Company Ltd was a British manufacturing company in Coventry from 1919 to 1967. In addition to automobiles designed for the civilian market, the company also produced racing cars, aircraft engines, armoured cars and other armoured fighting vehicles.
Document 9: Red Bull RB11: The Red Bull RB11 is a Formula One racing car designed by Adrian Newey for Infiniti Red Bull Racing to compete in the 2015 Formula One season. It was driven by Daniel Ricciardo and Daniil Kvyat. This was the last Red Bull car with engines badged as "Renault" and to feature their title sponsor Infiniti as they split from Red Bull at the end of the season due to a breakdown in the team's relationship with Renault.
Document 10: Colin Chapman: Anthony Colin Bruce Chapman CBE (19 May 1928 – 16 December 1982) was an influential English design engineer, inventor, and builder in the automotive industry, and founder of Lotus Cars.
Document 11: RE Amemiya: RE Amemiya Car Co Ltd (有限会社RE雨宮自動車 , Yūgen Kaisha Āru-ī Amemiya Jidōsha ) is an automotive tuning company from Chiba, Chiba Prefecture, Japan founded by Isami Amemiya. Amemiya has made a name for himself tuning rotary engines since 1974 and has become a pioneer in tuning rotary-powered Mazdas. Thirty years later, first on the street and later in the Super GT series, Amemiya has left its mark in the tuning and motorsports worlds for rotaries.
Document 12: Brabham: Motor Racing Developments Ltd., commonly known as Brabham , was a British racing car manufacturer and Formula One racing team. Founded in 1960 by two Australians, driver Jack Brabham and designer Ron Tauranac, the team won four Drivers' and two Constructors' World Championships in its 30-year Formula One history. Jack Brabham's 1966 Drivers' Championship remains the only such achievement using a car bearing the driver's own name.
Document 13: Cooper Car Company: The Cooper Car Company is a car manufacturer founded in December 1947 by Charles Cooper and his son John Cooper. Together with John's boyhood friend, Eric Brandon, they began by building racing cars in Charles's small garage in Surbiton, Surrey, England, in 1946. Through the 1950s and early 1960s they reached motor racing's highest levels as their rear-engined, single-seat cars altered the face of Formula One and the Indianapolis 500, and their dominated rally racing. Due in part to Cooper's legacy, Great Britain remains the home of a thriving racing industry, and the Cooper name lives on in the Cooper versions of the Mini production cars that are still built in England, but are now owned and marketed by BMW.
Document 14: Hersham and Walton Motors: Hersham and Walton Motors (HWM) is the world's longest established Aston Martin business (having acquired the franchise in 1951) and is well known as a racing car constructor. As a constructor, it is best known for its involvement in Formula Two from 1950 to 1953 and Formula One in 1954. When HWM owners George Abecassis and John Heath went racing together from 1946 and in 1948 they built a streamlined sports racing car on the chassis of a Sports Alta, and thus embarked upon the construction of racing cars and racing sports cars at their motor works in Walton-on-Thames, England. The 1948 car gave them encouraging results and so new car, this time called an HW-Alta, was constructed and raced in 1949; this car was sufficiently successful to convince the partners to embark upon building a full team of cars for the 1950 Formula Two season of British and continental events: these cars were known as HWMs.
Document 15: MK Indy: The MK Indy is a Lotus 7 replica based on the Locost principle, built by MK Sportscars in Maltby, Rotherham. The Indy has an independent rear suspension using the differential and drive shafts from a Ford Sierra. It uses many other components from the Sierra, including front hubs and steering rack. Further, it can be fitted with any of a variety of engines, the most popular choices being the Ford Pinto engine from the Sierra for its ease and cheapness or a large motorcycle engine for its light weight and high rpm.
ground_truth: Surbiton, Surrey, England