Extract the answer to the question from the following context. Question: What was the content of Book of Optics? Context: In the early 11th century, the Muslim physicist Ibn al-Haytham (Alhacen or Alhazen) discussed space perception and its epistemological implications in his Book of Optics (1021), he also rejected Aristotle's definition of topos (Physics IV) by way of geometric demonstrations and defined place as a mathematical spatial extension. His experimental proof of the intromission model of vision led to changes in the understanding of the visual perception of space, contrary to the previous emission theory of vision supported by Euclid and Ptolemy. In "tying the visual perception of space to prior bodily experience, Alhacen unequivocally rejected the intuitiveness of spatial perception and, therefore, the autonomy of vision. Without tangible notions of distance and size for correlation, sight can tell us next to nothing about such things."
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Answer: space perception

Extract the answer to the question from the following context. Question: Which Montana nickname implies that you see a lot of blue when you look up? Context: Montana i/mntn/ is a state in the Western region of the United States. The state's name is derived from the Spanish word montana (mountain). Montana has several nicknames, although none official, including "Big Sky Country" and "The Treasure State", and slogans that include "Land of the Shining Mountains" and more recently "The Last Best Place". Montana is ranked 4th in size, but 44th in population and 48th in population density of the 50 United States. The western third of Montana contains numerous mountain ranges. Smaller island ranges are found throughout the state. In total, 77 named ranges are part of the Rocky Mountains.
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Answer: Big Sky Country

Extract the answer to the question from the following context. Question: When does To Kill a Mockingbird happen? Context: The second part of the novel deals with what book reviewer Harding LeMay termed "the spirit-corroding shame of the civilized white Southerner in the treatment of the Negro". In the years following its release, many reviewers considered To Kill a Mockingbird a novel primarily concerned with race relations. Claudia Durst Johnson considers it "reasonable to believe" that the novel was shaped by two events involving racial issues in Alabama: Rosa Parks' refusal to yield her seat on a city bus to a white person, which sparked the 1955 Montgomery Bus Boycott, and the 1956 riots at the University of Alabama after Autherine Lucy and Polly Myers were admitted (Myers eventually withdrew her application and Lucy was expelled, but reinstated in 1980). In writing about the historical context of the novel's construction, two other literary scholars remark: "To Kill a Mockingbird was written and published amidst the most significant and conflict-ridden social change in the South since the Civil War and Reconstruction. Inevitably, despite its mid-1930s setting, the story told from the perspective of the 1950s voices the conflicts, tensions, and fears induced by this transition."
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Answer:
mid-1930s