Problem: Richard Feynman:

He immersed himself in work on the project, and was present at the Trinity bomb test. Feynman claimed to be the only person to see the explosion without the very dark glasses or welder's lenses provided, reasoning that it was safe to look through a truck windshield, as it would screen out the harmful ultraviolet radiation. On witnessing the blast, Feynman ducked towards the floor of his truck because of the immense brightness of the explosion, where he saw a temporary "purple splotch" afterimage of the event.

What was invisible to Feynman after the atomic test?
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A: unanswerable

Problem: The abomasum is the fourth and final stomach compartment in ruminants. It is a close equivalent of a monogastric stomach (e.g., those in humans or pigs), and digesta is processed here in much the same way. It serves primarily as a site for acid hydrolysis of microbial and dietary protein, preparing these protein sources for further digestion and absorption in the small intestine. Digesta is finally moved into the small intestine, where the digestion and absorption of nutrients occurs. Microbes produced in the reticulo-rumen are also digested in the small intestine.
What is also digested in the small intestine?
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Answer: Microbes produced in the reticulo-rumen are also digested in the small intestine

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Greater Richmond area is served by the Richmond International Airport (IATA: RIC, ICAO: KRIC), located in nearby Sandston, seven miles (11 km) southeast of Richmond and within an hour drive of historic Williamsburg, Virginia. Richmond International is now served by nine airlines with over 200 daily flights providing non-stop service to major destination markets and connecting flights to destinations worldwide. A record 3.3 million passengers used Richmond International Airport in 2006, a 13% increase over 2005.
What percentage increase in passenger traffic did Richmond International experience between 2005 and 2006?
A: 13

Context and question: The Arians no longer presented an unbroken front to their orthodox opponents. The Emperor Constantius, who had been the cause of so much trouble, died 4 November, 361 and was succeeded by Julian. The proclamation of the new prince's accession was the signal for a pagan outbreak against the still dominant Arian faction in Alexandria. George, the usurping Bishop, was flung into prison and murdered. An obscure presbyter of the name of Pistus was immediately chosen by the Arians to succeed him, when fresh news arrived that filled the orthodox party with hope. An edict had been put forth by Julian permitting the exiled bishops of the "Galileans" to return to their "towns and provinces". Athanasius received a summons from his own flock, and he accordingly re-entered his episcopal capitol on 22 February, 362.
Who succeeded Emperor Constantius?
Answer: Julian

Question: In 1695, the Scottish Parliament granted a charter to the Company of Scotland, which established a settlement in 1698 on the isthmus of Panama. Besieged by neighbouring Spanish colonists of New Granada, and afflicted by malaria, the colony was abandoned two years later. The Darien scheme was a financial disaster for Scotlanda quarter of Scottish capital was lost in the enterpriseand ended Scottish hopes of establishing its own overseas empire. The episode also had major political consequences, persuading the governments of both England and Scotland of the merits of a union of countries, rather than just crowns. This occurred in 1707 with the Treaty of Union, establishing the Kingdom of Great Britain.
Is there an answer to this question: When was Panama colonized by Scotland?

Answer: 1698

Question: Bal-musette is a style of French music and dance that first became popular in Paris in the 1870s and 1880s; by 1880 Paris had some 150 dance halls in the working-class neighbourhoods of the city. Patrons danced the bourree to the accompaniment of the cabrette (a bellows-blown bagpipe locally called a "musette") and often the vielle a roue (hurdy-gurdy) in the cafes and bars of the city. Parisian and Italian musicians who played the accordion adopted the style and established themselves in Auvergnat bars especially in the 19th arrondissement, and the romantic sounds of the accordion has since become one of the musical icons of the city. Paris became a major centre for jazz and still attracts jazz musicians from all around the world to its clubs and cafes.
Is there an answer to this question: in 1880, how many dance halls were in Paris?

Answer:
150