instruction:
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'.
question:
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?
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Answer: 1957


question:
Passage: Columbia (; ) is the female personification of the United States. It was also a historical name used to describe the Americas and the New World. It has given rise to the names of many persons, places, objects, institutions and companies; for example: Columbia University, the District of Columbia (the national capital of the United States), and the ship Columbia Rediviva, which would give its name to the Columbia River. Images of the Statue of Liberty largely displaced personified Columbia as the female symbol of the United States by around 1920, although Lady Liberty was seen as an aspect of Columbia. The District of Columbia is named after the personification, as is the traditional patriotic hymn "Hail Columbia", which is the official vice presidential anthem of the United States Vice President.
 Link Information: Established in 1754 Question: In what year was Columbia University founded?
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Answer: 1754 


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Passage: Within the regular series, the buildup to "Knightfall" begins with a six-issue run in Batman #484-489 (September 1992 - February 1993), in which Batman (at the onset of a personal psychological mid-life crisis) is forced to deal, in rapid succession, with the returning villain Black Mask and his gang (who target Bruce Wayne and Lucius Fox), a crazed killer called Metalhead, and a sharpshooter assassin hired by an imprisoned mobster to murder Commissioner Gordon. Batman begins to feel that he has lost his edge, especially after his failure to capture Black Mask. He finds himself unable to meditate or even focus. As Bruce Wayne, he contacts holistic therapist Shondra Kinsolving for treatment. He also assigns Robin (Tim Drake) to train Jean-Paul Valley in detective work to aid them as an ally, hoping to guide Valley's brainwashing away from making him a villainous threat. Despite the advice of everyone in his life, including Dr. Kinsolving, Bruce refuses to rest and continues to pursue his self-imposed duty despite his worsening condition (although not explicitly noted as a cause, these events take place immediately after the death of Superman, Batman's peer, elsewhere in the DC Universe).
 Link Information: none Question: How many months before the buildup to Knightfall did the death of Superman occur?
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Answer: none