In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.

Passage: By the 1920s, SCGX was doubling annually and had emerged as the "fastest growing grain market in the world"; transacting 22 million bushels in 1928 (valued at $336 million in 2018), resulting from its location in the heart of the Corn Belt and self-imposed standards before the Grain Standards Act of 1916 including species admittance and non-mixing. However, its growth was limited by shipping rates. With the trucking industry and Interstate Highway System not yet developed, SCGX was constrained by monopolized railroad rates, primarily by the Great Northern Railway. Exhausting their bargaining power with the Interstate Commerce Commission, SCGX President Charles C. Flanley directed future lobbying efforts to unlocking barge navigation of the Missouri River. His initiative was stalled throughout the 1930s by the Great Depression and Dust Bowl. In 1938, a renewed thirteen year campaign led by Secretary William Henry Marriott finally opened commercial navigation of the Missouri River and helped establish the Missouri River Basin Project, which included development of the Gavins Point Dam. The alternate transportation succeeded in breaking the railroad's monopoly. By the 1970s, SCGX was among the largest exchanges in the world; transacting over 100 million bushels annually (valued at $1 billion as of 2018).
 Link Information: The dam and hydroelectric power plant were constructed as the Gavins Point Project from 1952 to 1957 by the United States Army Corps of Engineers as part of the Pick-Sloan Plan Question: When was the dam that was part of the Missouri River Basin Project completed?
Answer: 1957

Passage: Duncan was born in Lebanon, Tennessee. His "paternal grandparents were small-areage farmers in Scott County, which in 1861 left Tennessee, refusing to follow the Volunteer State into the Confederacy, and declared itself 'the Free and Independent state of Scott.'" Duncan's parents were Lois (Swisher) and John Duncan Sr., who "hitchhiked into Knoxville with five dollars in his pocket,' and after an education at the University of Tennessee was elected mayor of Knoxville and then congressman." The elder Duncan was also a co-owner of the Knoxville Smokies of the "Sally League," for which his son "was a batboy, a ball shagger, scoreboard operator, and, as a freshman at the University of Tennessee, the Smokies' public-address announcer." Duncan also worked as a grocery bagger and salesman at Sears while working his way through school. Duncan supported Barry Goldwater's 1964 presidential campaign, and sent the first paycheck he earned as a bagboy at the local A&P to the Goldwater campaign.
 Link Information: none Question: How far is Knoxville from where Jimmy Duncan was born?
Answer: none

Passage: The garden already existed at least in the early 18th century. During the Austrian occupation of northern Serbia 1717-39, several hospitals were established in Belgrade, including the Great military hospital. Based on the Austrian plans, the hospital was set outside of the Belgrade Fortress ("Danubian" or "German Belgrade"), in the Serbian part of the city. As shown on the map of Belgrade by Nicolas François de Spar, the Tsarigrad Road began at the Württemberg Gate (Stambol Gate), at the modern Republic Square, and headed towards "Marko's cemetery" in Tašmajdan. The hospital was situated on the road's right side, where the modern Stari Dvor is located. Behind the hospital there was a large garden, predecessor of the modern park, and further behind it, across the road was the military cemetery. Later "Marko's market" developed on the spot and today it is the area surrounding the House of the National Assembly of Serbia. After Austria lost the Austro-Turkish War of 1737–1739, the northern Serbia, including Belgrade, was returned to the Turks. One of the provisions of the 1739 Treaty of Belgrade stated that Austria had to demolish all the fortifications and military and civilian buildings it has constructed during the occupation. Many Baroque buildings were demolished. However, Austria didn't demolish the buildings outside of the fortress walls, including the Great military hospital, which, albeit as a ruin, survived until the next Austrian occupation in 1788.
 Link Information: The Treaty of Belgrade, known as the Belgrade peace was the peace treaty signed on September 18, 1739 in Belgrade, Habsburg Kingdom of Serbia (today Serbia), by the Ottoman Empire on one side and the Habsburg Monarchy on the other Question: How many countries total were included in the Treaty?

Answer: 2