Problem: Vacuum:

In the medieval Middle Eastern world, the physicist and Islamic scholar, Al-Farabi (Alpharabius, 872950), conducted a small experiment concerning the existence of vacuum, in which he investigated handheld plungers in water.[unreliable source?] He concluded that air's volume can expand to fill available space, and he suggested that the concept of perfect vacuum was incoherent. However, according to Nader El-Bizri, the physicist Ibn al-Haytham (Alhazen, 9651039) and the Mu'tazili theologians disagreed with Aristotle and Al-Farabi, and they supported the existence of a void. Using geometry, Ibn al-Haytham mathematically demonstrated that place (al-makan) is the imagined three-dimensional void between the inner surfaces of a containing body. According to Ahmad Dallal, Abu Rayhan al-Biruni also states that "there is no observable evidence that rules out the possibility of vacuum". The suction pump later appeared in Europe from the 15th century.

In what century did Aristotle develop the suction pump?
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A: unanswerable

Problem: Pacific War:

Thus, only in 1944 did the U.S. Navy begin to use its 150 submarines to maximum effect: installing effective shipboard radar, replacing commanders deemed lacking in aggression, and fixing the faults in the torpedoes. Japanese commerce protection was "shiftless beyond description,"[nb 14] and convoys were poorly organized and defended compared to Allied ones, a product of flawed IJN doctrine and training errors concealed by American faults as much as Japanese overconfidence. The number of U.S. submarines patrols (and sinkings) rose steeply: 350 patrols (180 ships sunk) in 1942, 350 (335) in 1943, and 520 (603) in 1944. By 1945, sinkings of Japanese vessels had decreased because so few targets dared to venture out on the high seas. In all, Allied submarines destroyed 1,200 merchant ships about five million tons of shipping. Most were small cargo-carriers, but 124 were tankers bringing desperately needed oil from the East Indies. Another 320 were passenger ships and troop transports. At critical stages of the Guadalcanal, Saipan, and Leyte campaigns, thousands of Japanese troops were killed or diverted from where they were needed. Over 200 warships were sunk, ranging from many auxiliaries and destroyers to one battleship and no fewer than eight carriers.

How many Japanese carriers were sunk during the war?
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A: eight

Problem: YouTube:

YouTube Red is YouTube's premium subscription service. It offers advertising-free streaming, access to exclusive content, background and offline video playback on mobile devices, and access to the Google Play Music "All Access" service. YouTube Red was originally announced on November 12, 2014, as "Music Key", a subscription music streaming service, and was intended to integrate with and replace the existing Google Play Music "All Access" service. On October 28, 2015, the service was re-launched as YouTube Red, offering ad-free streaming of all videos, as well as access to exclusive original content.

What is YouTube Premium?
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A: unanswerable

Problem: Somerset:

There is an extensive network of caves, including Wookey Hole, underground rivers, and gorges, including the Cheddar Gorge and Ebbor Gorge. The county has many rivers, including the Axe, Brue, Cary, Parrett, Sheppey, Tone and Yeo. These both feed and drain the flat levels and moors of mid and west Somerset. In the north of the county the River Chew flows into the Bristol Avon. The Parrett is tidal almost to Langport, where there is evidence of two Roman wharfs. At the same site during the reign of King Charles I, river tolls were levied on boats to pay for the maintenance of the bridge.

Name some of the county rivers
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A:
the Axe, Brue, Cary, Parrett, Sheppey, Tone and Yeo