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: By the 1st century, Babylonia, to which Jews migrated to after the Babylonian conquest as well as after the Bar Kokhba revolt in 135 CE, already held a speedily growing population of an estimated 1,000,000 Jews, which increased to an estimated 2 million  between the years 200 CE – 500 CE, both by natural growth and by immigration of more Jews from the Land of Israel, making up about 1/6 of the world Jewish population at that era. At times conversion has accounted for a part of Jewish population growth. Some have claimed that in the 1st century of the Christian era, for example, the population more than doubled, from four to 8–10 million within the confines of the Roman Empire, in good part as a result of a wave of conversion.

A: Where did the Jews migrate to before the Babylonian conquest?
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Q: Passage: The traditional energy supply of Thuringia is lignite, mined in the bordering Leipzig region. Since 2000, the importance of environmentally unfriendly lignite combustion has declined in favour of renewable energies, which reached an amount of 40% (in 2013), and more clean gas combustion, often carried out as Cogeneration in the municipal power stations. The most important forms of renewable energies are Wind power and Biomass, followed by Solar energy and Hydroelectricity. Furthermore, Thuringia hosts two big pumped storage stations: the Goldisthal Pumped Storage Station and the Hohenwarte Dam.

A: What is Thuringia's new energy supply?
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Q: Passage: The region is home to about 2.5 million insect species, tens of thousands of plants, and some 2,000 birds and mammals. To date, at least 40,000 plant species, 2,200 fishes, 1,294 birds, 427 mammals, 428 amphibians, and 378 reptiles have been scientifically classified in the region. One in five of all the bird species in the world live in the rainforests of the Amazon, and one in five of the fish species live in Amazonian rivers and streams. Scientists have described between 96,660 and 128,843 invertebrate species in Brazil alone.

A:
The region is home to 25 million what?
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