This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

Q: Mahayana Buddhism received significant theoretical grounding from Nagarjuna (perhaps c. 150–250 CE), arguably the most influential scholar within the Mahayana tradition. Nagarjuna's primary contribution to Buddhist philosophy was the systematic exposition of the concept of śūnyatā, or "emptiness", widely attested in the Prajñāpāramitā sutras that emerged in his era. The concept of emptiness brings together other key Buddhist doctrines, particularly anatta and dependent origination, to refute the metaphysics of Sarvastivada and Sautrantika (extinct non-Mahayana schools). For Nagarjuna, it is not merely sentient beings that are empty of ātman; all phenomena (dharmas) are without any svabhava (literally "own-nature" or "self-nature"), and thus without any underlying essence; they are "empty" of being independent; thus the heterodox theories of svabhava circulating at the time were refuted on the basis of the doctrines of early Buddhism. Nagarjuna's school of thought is known as the Mādhyamaka. Some of the writings attributed to Nagarjuna made explicit references to Mahayana texts, but his philosophy was argued within the parameters set out by the agamas. He may have arrived at his positions from a desire to achieve a consistent exegesis of the Buddha's doctrine as recorded in the Canon. In the eyes of Nagarjuna the Buddha was not merely a forerunner, but the very founder of the Mādhyamaka system.

A: Nagarjuna's main contribution was the exposition of the concept of what?
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Q: In the first week of May 2013, Prime Minister Passos Coelho announced a significant government plan for the public sector, whereby 30,000 jobs will be cut and the number of weekly working hours will be increased from 35 to 40 hours. Coelho reaffirmed the announcement by explaining that austerity measures are necessary if Portugal seeks to avoid another monetary bailout grant from the European Commission, European Central Bank and International Monetary Fund—the overall plan intends to enact further cuts of €4.8 billion over a three-year period.

A: Who was the Portugal Prime Minister in 2013?
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Q: With the Japanese CAP out of position and the carriers at their most vulnerable, SBD Dauntlesses from Enterprise and Yorktown appeared at an altitude of 10,000 feet (3,000 m) and commenced their attack, quickly dealing fatal blows to three fleet carriers: Sōryū, Kaga, and Akagi. Within minutes, all three were ablaze and had to be abandoned with great loss of life. Hiryū managed to survive the wave of dive bombers and launched a counter-attack against the American carriers which caused severe damage to Yorktown (which was later finished off by a Japanese submarine). However, a second attack from the U.S. carriers a few hours later found and destroyed Hiryū, the last remaining fleet carrier available to Nagumo. With his carriers lost and the Americans withdrawn out of range of his powerful battleships, Yamamoto was forced to call off the operation, leaving Midway in American hands. The battle proved to be a decisive victory for the Allies. For the second time, Japanese expansion had been checked and its formidable Combined Fleet was significantly weakened by the loss of four fleet carriers and many highly trained, virtually irreplaceable, personnel. Japan would be largely on the defensive for the rest of the war.

A:
At what altitude did the American dive bombers commence their attck on the Japanese carriers?
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