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: Santa Monica was long inhabited by the Tongva people. Santa Monica was called Kecheek in the Tongva language. The first non-indigenous group to set foot in the area was the party of explorer Gaspar de Portolà, who camped near the present day intersection of Barrington and Ohio Avenues on August 3, 1769. There are two different versions of the naming of the city. One says that it was named in honor of the feast day of Saint Monica (mother of Saint Augustine), but her feast day is actually May 4. Another version says that it was named by Juan Crespí on account of a pair of springs, the Kuruvungna Springs (Serra Springs), that were reminiscent of the tears that Saint Monica shed over her son's early impiety.

A: What language did Gaspar de Portola speak?
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Q: Passage: Rendering software which cannot process a Unicode character appropriately often displays it as an open rectangle, or the Unicode "replacement character" (U+FFFD, �), to indicate the position of the unrecognized character. Some systems have made attempts to provide more information about such characters. The Apple's Last Resort font will display a substitute glyph indicating the Unicode range of the character, and the SIL International's Unicode Fallback font will display a box showing the hexadecimal scalar value of the character.

A:
What is the Unicode for an open rectangle?
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