Question: Who was president when statehood was awarded to the location of Knoxville Raceway?

full_context: Document 1: Iowa: Almost immediately after achieving territorial status, a clamor arose for statehood. On December 28, 1846, Iowa became the 29th state in the Union when President James K. Polk signed Iowa's admission bill into law. Once admitted to the Union, the state's boundary issues resolved, and most of its land purchased from the Indians, Iowa set its direction to development and organized campaigns for settlers and investors, boasting the young frontier state's rich farmlands, fine citizens, free and open society, and good government.
Document 2: History of Texas (1845–1860): The Republic of Texas had formed in 1836, after breaking away from Mexico in the Texas Revolution. The following year, an ambassador from Texas approached the United States about the possibility of becoming an American state. Fearing a war with Mexico, which did not recognize Texas independence, the United States declined the offer. In 1844, James K. Polk was elected the United States president after promising to annex Texas. Before he assumed office, the outgoing president, John Tyler, entered negotiations with Texas. On February 26, 1845, six days before Polk took office, the U.S. Congress approved the annexation. The Texas legislature approved annexation in July 1845 and constructed a state constitution. In October, Texas residents approved the annexation and the new constitution, and Texas was officially inducted into the United States on December 29, 1845.
Document 3: Knoxville Raceway: Knoxville Raceway is a semi-banked 1/2 mile dirt oval raceway (zook clay) located at the Marion County Fairgrounds in Knoxville, Iowa, United States. Races at the "Sprint Car Capital of the World" are held on Saturday nights from April through September each year. Some special events may start as early as Wednesday and build up to Saturday. Regular events include 305 cubic inch, 360 cubic inch and 410 cubic inch sprint car racing. Each August, the Raceway holds the paramount sprint car event in the United States, the Knoxville Nationals. The track is governed by the 24-member fair board elected by Marion County residents.
Document 4: Oklahoma City: Other major sporting events include Thoroughbred and Quarter horse racing circuits at Remington Park and numerous horse shows and equine events that take place at the state fairgrounds each year. There are numerous golf courses and country clubs spread around the city.
Document 5: Cornwall Motor Speedway: The Cornwall Motor Speedway is a 1/4 mile dirt track near the community of Cornwall, Ontario, Canada. It is located northwest of the city on Cornwall Centre Road. The track opened in 1970 and runs weekly racing on Sunday evenings.
Document 6: Minnesota: In 1762 the region became part of Spanish Louisiana until 1802. The portion of the state east of the Mississippi River became part of the United States at the end of the American Revolutionary War, when the Second Treaty of Paris was signed. Land west of the Mississippi River was acquired with the Louisiana Purchase, although a portion of the Red River Valley was disputed until the Treaty of 1818. By the late 1700s, the North West Company had established the post of Fort Charlotte at the Lake Superior end of the Grand Portage, until moving 50 miles northeast to Fort William in 1803. In 1805, Zebulon Pike bargained with Native Americans to acquire land at the confluence of the Minnesota and Mississippi rivers. The construction of Fort Snelling followed between 1819 and 1825. Its soldiers built a grist mill and a sawmill at Saint Anthony Falls, the first of the water-powered industries around which the city of Minneapolis later grew. Meanwhile, squatters, government officials, and tourists had settled near the fort. In 1839, the army forced them to move downriver and they settled in the area that became St. Paul. Minnesota Territory was formed on March 3, 1849. The first territorial legislature (held September 2, 1849) was dominated by men from New England or of New England ancestry. Thousands of people had come to build farms and cut timber, and Minnesota became the 32nd U.S. state on May 11, 1858. The founding population was so overwhelmingly of New England origins that the state was dubbed "the New England of the West".
Document 7: Potomac Speedway: Potomac Speedway is a 3/8 mile clay oval raceway located in Budds Creek, Maryland, near Charlotte Hall. The raceway was first raced on in 1973. Races are typically held on Friday or Saturday nights. Regular events include Super Late Models, Limited Late Models, Street Stocks, and Hobby Stocks and 4 cylinders. The speedway also holds events for Modifieds, Crate Late Models, Strictly Stocks and Hornets. Potomac Speedway has a seating capacity of about 4,000 in the main grandstands and can hold an additional 1,000 in the pit area.
Document 8: Des Moines, Iowa: On September 22, 1851, Des Moines was incorporated as a city; the charter was approved by voters on October 18. In 1857, the name ``Fort Des Moines ''was shortened to`` Des Moines'', and it was designated as the second state capital, previously at Iowa City. Growth was slow during the Civil War period, but the city exploded in size and importance after a railroad link was completed in 1866.
Document 9: Ohio: On February 19, 1803, U.S. President Thomas Jefferson signed an act of Congress that approved Ohio's boundaries and constitution. However, Congress had never passed a resolution formally admitting Ohio as the 17th state. The current custom of Congress declaring an official date of statehood did not begin until 1812, with Louisiana's admission as the 18th state. Although no formal resolution of admission was required, when the oversight was discovered in 1953, Ohio congressman George H. Bender introduced a bill in Congress to admit Ohio to the Union retroactive to March 1, 1803, the date on which the Ohio General Assembly first convened. At a special session at the old state capital in Chillicothe, the Ohio state legislature approved a new petition for statehood that was delivered to Washington, D.C. on horseback. On August 7, 1953 (the year of Ohio's 150th anniversary), President Eisenhower signed a congressional joint resolution that officially declared March 1, 1803, the date of Ohio's admittance into the Union.
Document 10: Indiana: In order to decrease the threat of Indian raids following the Battle of Tippecanoe, Corydon, a town in the far southern part of Indiana, was named the second capital of the Indiana Territory in May 1813. Two years later, a petition for statehood was approved by the territorial general assembly and sent to Congress. An Enabling Act was passed to provide an election of delegates to write a constitution for Indiana. On June 10, 1816, delegates assembled at Corydon to write the constitution, which was completed in 19 days. President James Madison approved Indiana's admission into the union as the nineteenth state on December 11, 1816. In 1825, the state capital was moved from Corydon to Indianapolis.
Document 11: History of Idaho: When President Benjamin Harrison signed the law admitting Idaho as a U.S. state on July 3, 1890, the population was 88,548. George L. Shoup became the state's first governor, but resigned after only a few weeks in office to take a seat in the United States Senate.
Document 12: Bristol Motor Speedway: Bristol Motor Speedway, formerly known as Bristol International Raceway and Bristol Raceway, is a NASCAR short track venue located in Bristol, Tennessee. Constructed in 1960, it held its first NASCAR race on July 30, 1961. Despite its short length, Bristol is among the most popular tracks on the NASCAR schedule because of its distinct features, which include extraordinarily steep banking, an all concrete surface, two pit roads, and stadium - like seating. It has also been named one of the loudest NASCAR tracks.
Document 13: Beaver Dam Raceway: Beaver Dam Raceway is a one-third mile banked clay oval track located in Beaver Dam, Wisconsin, U.S.A.. The track holds weekly races over the Northern American summer months. It hosts an annual World of Outlaws sprint car races. The 2013 U.S. Dirt Legends Nationals event was held at the track.
Document 14: Tucson, Arizona: Tracks include Tucson Raceway Park and Rillito Downs. Tucson Raceway Park hosts NASCAR-sanctioned auto racing events and is one of only two asphalt short tracks in Arizona. Rillito Downs is an in-town destination on weekends in January and February each year. This historic track held the first organized quarter horse races in the world, and they are still racing there. The racetrack is threatened by development. The Moltacqua racetrack, was another historic horse racetrack located on what is now Sabino Canyon Road and Vactor Ranch Trail, but it no longer exists.
Document 15: Exhibition game: Various auto racing organizations hold exhibition events; these events usually award no championship points to participants, but they do offer prize money to participants. The NASCAR Sprint Cup Series holds two exhibition events annually - the Sprint Unlimited, held at Daytona International Speedway at the start of the season, and the NASCAR Sprint All-Star Race, held at Charlotte Motor Speedway midway through the season. Both events carry a hefty purse of over USD $1,000,000. NASCAR has also held exhibition races at Suzuka Circuit and Twin Ring Motegi in Japan and Calder Park Thunderdome in Australia.
ground_truth: President James K. Polk
sub_queries: In which state is Knoxville Raceway located? Answer: Iowa
who was president when Iowa became a state Answer: President James K. Polk