This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Q: Passage: Unveiled in 1888, Royal Arsenal's first crest featured three cannon viewed from above, pointing northwards, similar to the coat of arms of the Metropolitan Borough of Woolwich (nowadays transferred to the coat of arms of the Royal Borough of Greenwich). These can sometimes be mistaken for chimneys, but the presence of a carved lion's head and a cascabel on each are clear indicators that they are cannon. This was dropped after the move to Highbury in 1913, only to be reinstated in 1922, when the club adopted a crest featuring a single cannon, pointing eastwards, with the club's nickname, The Gunners, inscribed alongside it; this crest only lasted until 1925, when the cannon was reversed to point westward and its barrel slimmed down.

A: In what year did the Metropolitan Borough of Woolwich develop its coat of arms?
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Q: Passage: Approximately 10,000 years ago, desertification forced hunter-gatherer societies south into the Sahel regions of northern Central Africa, where some groups settled and began farming as part of the Neolithic Revolution. Initial farming of white yam progressed into millet and sorghum, and before 3000 BC the domestication of African oil palm improved the groups' nutrition and allowed for expansion of the local populations. Bananas arrived in the region and added an important source of carbohydrates to the diet; they were also used in the production of alcoholic beverages.[when?] This Agricultural Revolution, combined with a "Fish-stew Revolution", in which fishing began to take place, and the use of boats, allowed for the transportation of goods. Products were often moved in ceramic pots, which are the first known examples of artistic expression from the region's inhabitants.

A: How long ago did farming force hunter-gatherer societies south?
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Q: Passage: Earth's surface and the clouds absorb visible and invisible radiation from the sun and re-emit much of the energy as infrared back to atmosphere. Certain substances in the atmosphere, chiefly cloud droplets and water vapor, but also carbon dioxide, methane, nitrous oxide, sulfur hexafluoride, and chlorofluorocarbons, absorb this infrared, and re-radiate it in all directions including back to Earth. Thus, the greenhouse effect keeps the atmosphere and surface much warmer than if the infrared absorbers were absent from the atmosphere.

A:
What does the greenhouse effect absorb from the sun?
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