Question: The American Stock Car Racing Association was formed in a city that is the seat of which county ?
Context: Larry "Butch" Hartman (May 11, 1940 – December 21, 1994) was an American stock car racing national champion in the United States Automobile Club (USAC) from Zanesville, Ohio.  After winning the USAC Stock Car Rookie of the Year award in 1966, the series' Most Improved Driver in 1967, and its Most Outstanding Driver the following year.  He won five USAC Stock car national titles in the 1970s.  Hartman had the fourth highest number of USAC Stock car wins in the series' history.  Hartman raced in twenty NASCAR stock car races; his highest finish was a fifth-place run at National 500 at Charlotte Motor Speedway (now Lowe's Motor Speedway).  Hartman worked full-time at his father's company, building his own engines and towing his cars to the track each weekend.  In 1968, he became the first rookie to lead the Daytona 500. V8 Hotstox is a British stock car racing formula that races on British short oval racing circuits.  Drivers are members of the British Stock Car Drivers Association (BSCDA) and are affiliated to the British Stock Car Racing Association (BriSCA).  V8 Hotstox have also previously been known as V8 Stock Cars.  (www.v8hotstox.com) Trenton is the capital city of the U.S. state of New Jersey and the county seat of Mercer County.  It was briefly the capital of the United States.  The city's metropolitan area is grouped with the New York metropolitan area by the United States Census Bureau, but directly borders the Philadelphia metropolitan area and is part of the Federal Communications Commission's Philadelphia Designated Market Area.  As of the 2010 United States Census, Trenton had a population of 84,913, making it the state's 10th-largest municipality.  The Census Bureau estimated that the city's population was 84,034 in 2014. Gerald "Jerry" Nadeau (born September 9, 1970) is a former American stock car racer from Danbury, Connecticut.  He competed in the NASCAR Winston Cup Series (now Monster Energy NASCAR Cup Series).  He started racing in karting before moving up to car racing, driving in the 12 Hours of Sebring, the European Formula Ford Festival, and the Barber Dodge Pro Series.  Nadeau arrived in NASCAR, the highest and most expensive level of stock car racing in the United States, with a limited budget.  He started racing part-time in NASCAR and finished sixth in the 1996 Formula Opel Euro Series. The American Stock Car Racing Association (ASCRA) was formed in Trenton, New Jersey in August/September 1947 by the owners and drivers of stock cars for the betterment of the sport.  The officers for the first season were Leon McBride President, Paul Barbiche First Vice President, Charles DiNatale Second Vice President, Rocky DiNatale Treasurer, and William Streeter Secretary.  The first event was Sunday October 5 at Flemington Fairgrounds, New Jersey.  The winner of the darkness shortened feature was Tommy Bradshaw of Trenton, New Jersey. Tommy Coates (May 28, 1909 - November 1, 1980) of Trenton, New Jersey was a stock car racer.  He was the 1951 Langhorne NASCAR sportsman champion on the 1/4 mile Yellow Jacket Circuit.  Originally from San Antonio Texas, he competed in stock car races in 1940 and 1941.  He joined up with the American Stock Car Racing Association (ASCRA) in 1947, eventually becoming secretary of the organization in 1950. Stock car racing is a form of automobile racing found mainly and most prominently in the United States and Canada, with Australia, New Zealand and Brazil also having forms of stock car auto racing.  Traditionally, races are run on oval tracks measuring approximately 0.25 to .  The world's largest governing body for stock car racing is the American NASCAR, and its Monster Energy NASCAR Cup Series is the premier top level series of professional stock car racing.  Top level races typically range between 200 to in length. Floyd Sam Nunis (December 16, 1903 – February 1, 1980) was a pioneering figure in American stock car racing, being involved in both the American Automobile Association and the National Stock Car Racing Association. Ed Samples (January 31, 1921 – June 10, 1991) was a pioneering American stock car driver, who competed in NSCRA and NASCAR events in the 1940s and early 1950s.  He was the winner of the 1946 stock car racing championship, and later won the 1949 National Stock Car Racing Association championship. The National Stock Car Racing Association (NSRA/NSCRA) was a sanctioning body for stock car racing that operated in the Southeastern United States during the late 1940s and early 1950s.  Competing against several other sanctioning bodies, including NASCAR, NSCRA was considered to be the most significant challenge to NASCAR's dominance of the sport; however it proved incapable of competing with the larger sanction, and closed down midway through the 1951 racing season.
Answer: Mercer County