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: In 1872, Russian Alexander Lodygin invented an incandescent light bulb and obtained a Russian patent in 1874. He used as a burner two carbon rods of diminished section in a glass receiver, hermetically sealed, and filled with nitrogen, electrically arranged so that the current could be passed to the second carbon when the first had been consumed. Later he lived in the USA, changed his name to Alexander de Lodyguine and applied and obtained patents for incandescent lamps having chromium, iridium, rhodium, ruthenium, osmium, molybdenum and tungsten filaments, and a bulb using a molybdenum filament was demonstrated at the world fair of 1900 in Paris.

A: Who did not patent an incandescent light bulb in 1872?
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Q: Passage: The best, worst and average case complexity refer to three different ways of measuring the time complexity (or any other complexity measure) of different inputs of the same size. Since some inputs of size n may be faster to solve than others, we define the following complexities:

A: What are the three secondary expressions used to represent case complexity?
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Q: Passage: Himachal was one of the few states that had remained largely untouched by external customs, largely due to its difficult terrain. With the technological advancements the state has changed very rapidly. It is a multireligional, multicultural as well as multilingual state like other Indian states. Some of the most commonly spoken languages includes Hindi, Pahari, Dogri, Mandeali Kangri, Mandyali, Gojri and Kinnauri. The caste communities residing in Himachal include the Khatri, Brahmins of the Hindu Faith and the Sikh Brahmin Caste Bhatra, Rajputs, Gujjars, Gaddis, Ghirth (choudhary), Kannets, Rathis and Kolis, Sood There are tribal populations in the state which mainly comprise Kinnars, Pangawals, Sulehria, and Lahaulis.The people Of Himachal Pradesh are very simple and live a traditional 'Pahari' lifestyle.

A:
Why was Dogri untouched by external customs?
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