Question: What was the population in 1900 of the second largest city in the US state having the Library District of the county containing Yuma?

Knowledge 1: Yuma County Library District
The Yuma County Library District serves the population of Yuma County, Arizona. Today the library district consists of the nearly 80,000 square foot Main Library located in Yuma as well as branches in downtown Yuma, the Foothills, Somerton, San Luis, Wellton, Dateland, and Roll. The first Yuma Library, a Carnegie library, opened February 24, 1921 with 1,053 volumes and seating for 20 persons. Located in Sunset Park, the Yuma Carnegie Library underwent several expansions and renovations over the years, including a $4.2 million renovation completed in 2009. The Yuma Carnegie library still operates today as the Heritage Branch Library in downtown Yuma. [SEP] Knowledge 2: Tucson, Arizona
By 1900, 7,531 people lived in the city. The population increased gradually to 13,913 in 1910. At about this time, the U.S. Veterans Administration had begun construction on the present Veterans Hospital. Many veterans who had been gassed in World War I and were in need of respiratory therapy began coming to Tucson after the war, due to the clean dry air. Over the following years the city continued to grow, with the population increasing to 20,292 in 1920 and 36,818 in 1940. In 2006 the population of Pima County, in which Tucson is located, passed one million while the City of Tucson's population was 535,000. [SEP] Knowledge 3: Yuma, Colorado
The City of Yuma is a Home Rule Municipality that is the most populous city in Yuma County, Colorado, United States. The population was 3,524 at the 2010 census. [SEP] Knowledge 4: Tucson, Arizona
Tucson is located 118 mi (190 km) southeast of Phoenix and 60 mi (97 km) north of the United States - Mexico border. The 2010 United States Census puts the city's population at 520,116 with a metropolitan area population at 980,263. In 2009, Tucson ranked as the 32nd largest city and 52nd largest metropolitan area in the United States. A major city in the Arizona Sun Corridor, Tucson is the largest city in southern Arizona, the second largest in the state after Phoenix. It is also the largest city in the area of the Gadsden Purchase. As of 2015, The Greater Tucson Metro area has exceeded a population of 1 million.
Knowledge 1: Yuma County Library District
The Yuma County Library District serves the population of Yuma County, Arizona. Today the library district consists of the nearly 80,000 square foot Main Library located in Yuma as well as branches in downtown Yuma, the Foothills, Somerton, San Luis, Wellton, Dateland, and Roll. The first Yuma Library, a Carnegie library, opened February 24, 1921 with 1,053 volumes and seating for 20 persons. Located in Sunset Park, the Yuma Carnegie Library underwent several expansions and renovations over the years, including a $4.2 million renovation completed in 2009. The Yuma Carnegie library still operates today as the Heritage Branch Library in downtown Yuma. [SEP] Knowledge 2: Tucson, Arizona
Tucson is located 118 mi (190 km) southeast of Phoenix and 60 mi (97 km) north of the United States - Mexico border. The 2010 United States Census puts the city's population at 520,116 with a metropolitan area population at 980,263. In 2009, Tucson ranked as the 32nd largest city and 52nd largest metropolitan area in the United States. A major city in the Arizona Sun Corridor, Tucson is the largest city in southern Arizona, the second largest in the state after Phoenix. It is also the largest city in the area of the Gadsden Purchase. As of 2015, The Greater Tucson Metro area has exceeded a population of 1 million. [SEP] Knowledge 3: Tucson, Arizona
By 1900, 7,531 people lived in the city. The population increased gradually to 13,913 in 1910. At about this time, the U.S. Veterans Administration had begun construction on the present Veterans Hospital. Many veterans who had been gassed in World War I and were in need of respiratory therapy began coming to Tucson after the war, due to the clean dry air. Over the following years the city continued to grow, with the population increasing to 20,292 in 1920 and 36,818 in 1940. In 2006 the population of Pima County, in which Tucson is located, passed one million while the City of Tucson's population was 535,000. [SEP] Knowledge 4: Yuma, Colorado
The City of Yuma is a Home Rule Municipality that is the most populous city in Yuma County, Colorado, United States. The population was 3,524 at the 2010 census.
Knowledge 1: Yuma County Library District
The Yuma County Library District serves the population of Yuma County, Arizona. Today the library district consists of the nearly 80,000 square foot Main Library located in Yuma as well as branches in downtown Yuma, the Foothills, Somerton, San Luis, Wellton, Dateland, and Roll. The first Yuma Library, a Carnegie library, opened February 24, 1921 with 1,053 volumes and seating for 20 persons. Located in Sunset Park, the Yuma Carnegie Library underwent several expansions and renovations over the years, including a $4.2 million renovation completed in 2009. The Yuma Carnegie library still operates today as the Heritage Branch Library in downtown Yuma. [SEP] Knowledge 2: Tucson, Arizona
Tucson is located 118 mi (190 km) southeast of Phoenix and 60 mi (97 km) north of the United States - Mexico border. The 2010 United States Census puts the city's population at 520,116 with a metropolitan area population at 980,263. In 2009, Tucson ranked as the 32nd largest city and 52nd largest metropolitan area in the United States. A major city in the Arizona Sun Corridor, Tucson is the largest city in southern Arizona, the second largest in the state after Phoenix. It is also the largest city in the area of the Gadsden Purchase. As of 2015, The Greater Tucson Metro area has exceeded a population of 1 million. [SEP] Knowledge 3: Tucson, Arizona
By 1900, 7,531 people lived in the city. The population increased gradually to 13,913 in 1910. At about this time, the U.S. Veterans Administration had begun construction on the present Veterans Hospital. Many veterans who had been gassed in World War I and were in need of respiratory therapy began coming to Tucson after the war, due to the clean dry air. Over the following years the city continued to grow, with the population increasing to 20,292 in 1920 and 36,818 in 1940. In 2006 the population of Pima County, in which Tucson is located, passed one million while the City of Tucson's population was 535,000. [SEP] Knowledge 4: United States
The United States of America (USA), commonly known as the United States (U.S.) or America, is a federal republic composed of 50 states, a federal district, five major self - governing territories, and various possessions. At 3.8 million square miles (9.8 million km) and with over 325 million people, the United States is the world's third - or fourth - largest country by total area and the third-most populous. The capital is Washington, D.C., and the largest city by population is New York City. Forty - eight states and the capital's federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The state of Hawaii is an archipelago in the mid-Pacific Ocean. The U.S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The extremely diverse geography, climate, and wildlife of the United States make it one of the world's 17 megadiverse countries.

Answer: 7,531