Question: At the start of the 20th Century, how many square kilometers was the city that contains the university where Charles Oakley was educated?

full_context: Document 1: Richmond, Virginia: Law and finance have long been driving forces in the economy. The city is home to both the United States Court of Appeals for the Fourth Circuit, one of 13 United States courts of appeals, and the Federal Reserve Bank of Richmond, one of 12 Federal Reserve Banks, as well as offices for international companies such as Genworth Financial, CapitalOne, Philip Morris USA, and numerous other banks and brokerages. Richmond is also home to four of the largest law firms in the United States: Hunton & Williams, McGuireWoods, Williams Mullen, and LeClairRyan. Another law firm with a major Richmond presence is Troutman Sanders, which merged with Richmond-based Mays & Valentine LLP in 2001.
Document 2: Richmond, Virginia: Richmond's economy is primarily driven by law, finance, and government, with federal, state, and local governmental agencies, as well as notable legal and banking firms, located in the downtown area. The city is home to both the United States Court of Appeals for the Fourth Circuit, one of 13 United States courts of appeals, and the Federal Reserve Bank of Richmond, one of 12 Federal Reserve Banks. Dominion Resources and MeadWestvaco, Fortune 500 companies, are headquartered in the city, with others in the metropolitan area.
Document 3: Terry Davis (basketball): Like two similar players, Charles Oakley before him and Ben Wallace (also undrafted) after him, Davis attended Virginia Union University and made a name for himself as a hard-nosed defensive player and rebounder.
Document 4: Richmond, Virginia: The site of Richmond had been an important village of the Powhatan Confederacy, and was briefly settled by English colonists from Jamestown in 1609, and in 1610–1611. The present city of Richmond was founded in 1737. It became the capital of the Colony and Dominion of Virginia in 1780. During the Revolutionary War period, several notable events occurred in the city, including Patrick Henry's "Give me liberty or give me death" speech in 1775 at St. John's Church, and the passage of the Virginia Statute for Religious Freedom written by Thomas Jefferson. During the American Civil War, Richmond served as the capital of the Confederate States of America. The city entered the 20th century with one of the world's first successful electric streetcar systems, as well as a national hub of African-American commerce and culture, the Jackson Ward neighborhood.
Document 5: Duane Ferrell: Duane Ferrell was never drafted but found his way into the NBA after being signed as a free agent by the Atlanta Hawks in 1988.
Document 6: James Davis (cornerback): James Steven Davis (born June 12, 1957 in Los Angeles, California) is a former American football cornerback with the Los Angeles Raiders of the National Football League. He attended Southern University.
Document 7: Roberts Vaux: He was born in Philadelphia, Pennsylvania, the eldest son of a well-known Quaker family (Richard and Anne Roberts Vaux) and connected by marriage to another such family, the Wistars. He received his education at private schools of Philadelphia.
Document 8: Richmond, Virginia: By the beginning of the 20th century, the city's population had reached 85,050 in 5 square miles (13 km2), making it the most densely populated city in the Southern United States. In 1900, the Census Bureau reported Richmond's population as 62.1% white and 37.9% black. Freed slaves and their descendants created a thriving African-American business community, and the city's historic Jackson Ward became known as the "Wall Street of Black America." In 1903, African-American businesswoman and financier Maggie L. Walker chartered St. Luke Penny Savings Bank, and served as its first president, as well as the first female bank president in the United States. Today, the bank is called the Consolidated Bank and Trust Company, and it is the oldest surviving African-American bank in the U.S. Other figures from this time included John Mitchell, Jr. In 1910, the former city of Manchester was consolidated with the city of Richmond, and in 1914, the city annexed Barton Heights, Ginter Park, and Highland Park areas of Henrico County. In May 1914, Richmond became the headquarters of the Fifth District of the Federal Reserve Bank.
Document 9: Robert Mardian: Robert Mardian went to public school in Pasadena, California followed by Columbia University, North Dakota State Teachers College, and the University of California, Los Angeles. While serving in the United States Navy he met and married Dorothy Denniss in 1946. They had three sons. Mardian was awarded a law degree from the University of Southern California in 1949. After leaving law school he went into private practice as a corporate lawyer.
Document 10: Richmond, Virginia: Richmond emerged a decade after the smoldering rubble of the Civil War to resume its position as an economic powerhouse, with iron front buildings and massive brick factories. Canal traffic peaked in the 1860s and slowly gave way to railroads, allowing Richmond to become a major railroad crossroads, eventually including the site of the world's first triple railroad crossing. Tobacco warehousing and processing continued to play a role, boosted by the world's first cigarette-rolling machine, invented by James Albert Bonsack of Roanoke in 1880/81. Contributing to Richmond's resurgence was the first successful electrically powered trolley system in the United States, the Richmond Union Passenger Railway. Designed by electric power pioneer Frank J. Sprague, the trolley system opened its first line in 1888, and electric streetcar lines rapidly spread to other cities across the country. Sprague's system used an overhead wire and trolley pole to collect current, with electric motors on the car's trucks. In Richmond, the transition from streetcars to buses began in May 1947 and was completed on November 25, 1949.
Document 11: Darryl Dawkins: Darryl Dawkins (January 11, 1957 – August 27, 2015) was an American professional basketball player, most noted for his days with the National Basketball Association's Philadelphia 76ers and New Jersey Nets, although he also played briefly for the Detroit Pistons and Utah Jazz late in his career. His nickname, "Chocolate Thunder", was bestowed upon him by Stevie Wonder. He was known for his powerful dunks, which led to the NBA adopting breakaway rims due to his shattering the backboard on two occasions in 1979.
Document 12: Robert Lee Vann: He was born in Ahoskie, North Carolina, the son of Lucy Peoples and an unknown father. He graduated as valedictorian of Waters Training School in Winton, North Carolina, in 1901, and attended Wayland Academy and Virginia Union University in Richmond, Virginia, from 1901 to 1903. He then attended Western University of Pennsylvania, (now the University of Pittsburgh) and graduated from its law school in 1909. He passed the bar examination in 1909 and married Jessie Matthews from Gettysburg, Pennsylvania, on February 17, 1919.
Document 13: George Watts Hill: Born in New York City, the son of John Sprunt Hill and Annie Louise Watts, George Watts Hill grew up in Durham and attended the University of North Carolina at Chapel Hill where he earned a Bachelor of Science in Commerce in 1922 and law degree in 1924. At UNC he was a member of Sigma Alpha Epsilon fraternity. He married Ann Austin McCulloch on September 30, 1924. Following a ten-month honeymoon around the world, the couple made their home in Harwood Hall, the mansion that his grandfather, George Washington Watts, had built.
Document 14: Jodi Rell: Born Mary Carolyn Reavis in Norfolk, Virginia, Rell attended Old Dominion University, but left in 1967 to marry Lou Rell, a U.S. Navy pilot. The couple first moved to New Jersey, where Lou Rell took a position as a commercial airline pilot with Trans World Airlines. The family then moved to a 19th-century farmhouse in Brookfield, Connecticut in 1969. Jodi Rell later attended, but did not graduate from, Western Connecticut State University. She received honorary law doctorates from the University of Hartford in 2001 and the University of New Haven in 2004. In 2015 she received an honorary doctorate degree of humane letters from Western Connecticut State University. In her early career, she tutored and did substitute work for the Hartford Public Schools.
Document 15: Backboard shattering: Darryl Dawkins became famous for shattering backboards, and is credited for being the one person to cause the NBA to introduce ``breakaway rims ''. Shaquille O'Neal slam dunked so hard that he broke the supports holding two backboards during games against the New Jersey Nets and the Phoenix Suns during the 1992 -- 93 NBA season.
ground_truth: 13
sub_queries: Charles Oakley >> educated at Answer: Virginia Union University
Virginia Union University >> located in the administrative territorial entity Answer: Richmond
How many square kilometers was Richmond at the start of the 20th century? Answer: 13