Problem: Extract the answer to the question from the following context. Question: The Persian Revolt led to which person taking over Media? Context: In 550 BC, Cyrus the Great, son of Mandane and Cambyses I, took over the Median Empire, and founded the Achaemenid Empire by unifying other city states. The conquest of Media was a result of what is called the Persian Revolt. The brouhaha was initially triggered by the actions of the Median ruler Astyages, and was quickly spread to other provinces, as they allied with the Persians. Later conquests under Cyrus and his successors expanded the empire to include Lydia, Babylon, Egypt, parts of the Balkans and Eastern Europe proper, as well as the lands to the west of the Indus and Oxus rivers.

A: Cyrus the Great

Problem: 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."

A: space perception

Problem: Extract the answer to the question from the following context. Question: Stalin was like the Nazis in that he was prejudiced against? Context: Regarding the timing of German rapprochement, many historians agree that the dismissal of Maxim Litvinov, whose Jewish ethnicity was viewed unfavorably by Nazi Germany, removed an obstacle to negotiations with Germany. Stalin immediately directed Molotov to "purge the ministry of Jews." Given Litvinov's prior attempts to create an anti-fascist coalition, association with the doctrine of collective security with France and Britain, and pro-Western orientation by the standards of the Kremlin, his dismissal indicated the existence of a Soviet option of rapprochement with Germany.[f] Likewise, Molotov's appointment served as a signal to Germany that the USSR was open to offers. The dismissal also signaled to France and Britain the existence of a potential negotiation option with Germany. One British official wrote that Litvinov's disappearance also meant the loss of an admirable technician or shock-absorber, while Molotov's "modus operandi" was "more truly Bolshevik than diplomatic or cosmopolitan." Carr argued that the Soviet Union's replacement of Foreign Minister Litvinov with Molotov on May 3, 1939 indicated not an irrevocable shift towards alignment with Germany, but rather was Stalin's way of engaging in hard bargaining with the British and the French by appointing a proverbial hard man, namely Molotov, to the Foreign Commissariat. Historian Albert Resis stated that the Litvinov dismissal gave the Soviets freedom to pursue faster-paced German negotiations, but that they did not abandon BritishFrench talks. Derek Watson argued that Molotov could get the best deal with Britain and France because he was not encumbered with the baggage of collective security and could negotiate with Germany. Geoffrey Roberts argued that Litvinov's dismissal helped the Soviets with BritishFrench talks, because Litvinov doubted or maybe even opposed such discussions.

A: Jews

Problem: Extract the answer to the question from the following context. Question: Which empire lasted longest? Context: Guinea-Bissau was once part of the kingdom of Gabu, part of the Mali Empire; parts of this kingdom persisted until the 18th century. Other parts of the territory in the current country were considered by the Portuguese as part of their empire. Portuguese Guinea was known as the Slave Coast, as it was a major area for the exportation of African slaves by Europeans to the western hemisphere. Previously slaves had been traded by Arabs north to the northern part of Africa and into the Middle East.

A:
Portuguese