Here is a question about this article: The largest opera houses of Paris are the 19th-century Opéra Garnier (historical Paris Opéra) and modern Opéra Bastille; the former tends toward the more classic ballets and operas, and the latter provides a mixed repertoire of classic and modern. In middle of the 19th century, there were three other active and competing opera houses: the Opéra-Comique (which still exists), Théâtre-Italien, and Théâtre Lyrique (which in modern times changed its profile and name to Théâtre de la Ville). Philharmonie de Paris, the modern symphonic concert hall of Paris, opened in January 2015. Another musical landmark is the Théâtre des Champs-Élysées, where the first performances of Diaghilev's Ballets Russes took place in 1913.
What is the answer to this question: What are the two largest opera houses in Paris?
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So... Opéra Garnier (historical Paris Opéra) and modern Opéra Bastille;


Here is a question about this article: Directly underneath the State Apartments is a suite of slightly less grand rooms known as the semi-state apartments. Opening from the Marble Hall, these rooms are used for less formal entertaining, such as luncheon parties and private audiences. Some of the rooms are named and decorated for particular visitors, such as the 1844 Room, decorated in that year for the State visit of Tsar Nicholas I of Russia, and, on the other side of the Bow Room, the 1855 Room, in honour of the visit of Emperor Napoleon III of France. At the centre of this suite is the Bow Room, through which thousands of guests pass annually to the Queen's Garden Parties in the Gardens. The Queen and Prince Philip use a smaller suite of rooms in the north wing.
What is the answer to this question: Which rooms are used for less formal entertaining such as luncheons or private audiences?
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So... the semi-state apartments


Here is a question about this article: Allied submarines did not adopt a defensive posture and wait for the enemy to attack. Within hours after the Pearl Harbor attack, in retribution against Japan, Roosevelt promulgated a new doctrine: unrestricted submarine warfare against Japan. This meant sinking any warship, commercial vessel, or passenger ship in Axis-controlled waters, without warning and without help to survivors.[nb 13] At the outbreak of the war in the Pacific the Dutch Admiral in charge of the naval defense of the East Indies, Conrad Helfrich, gave instructions to wage war aggressively. His small force of submarines sank more Japanese ships in the first weeks of the war than the entire British and US navies together, an exploit which earned him the nickname "Ship-a-day Helfrich". The Dutch force were in fact the first to sink an enemy warship; On 24 December 1941, HNLMS K XVI torpedoed and sank the Japanese destroyer Sagiri.
What is the answer to this question: When was the first Japanese warship sunk by a submarine?
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So...
24 December 1941