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: Static analysis techniques for software verification can be applied also in the scenario of query languages. In particular, the *Abstract interpretation framework has been extended to the field of query languages for relational databases as a way to support sound approximation techniques. The semantics of query languages can be tuned according to suitable abstractions of the concrete domain of data. The abstraction of relational database system has many interesting applications, in particular, for security purposes, such as fine grained access control, watermarking, etc.

A: Why is static analysis impossible with query languages?
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Q: Passage: In Armenia Russian has no official status, but it's recognised as a minority language under the Framework Convention for the Protection of National Minorities. According to estimates from Demoskop Weekly, in 2004 there were 15,000 native speakers of Russian in the country, and 1 million active speakers. 30% of the population was fluent in Russian in 2006, and 2% used it as the main language with family, friends or at work. Russian is spoken by 1.4% of the population according to a 2009 estimate from the World Factbook.

A: How many people read Demoskop Weekly in 2004?
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Q: Passage: Glacial abrasion is commonly characterized by glacial striations. Glaciers produce these when they contain large boulders that carve long scratches in the bedrock. By mapping the direction of the striations, researchers can determine the direction of the glacier's movement. Similar to striations are chatter marks, lines of crescent-shape depressions in the rock underlying a glacier. They are formed by abrasion when boulders in the glacier are repeatedly caught and released as they are dragged along the bedrock.

A:
What charactrerizes glacial striations?
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