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.
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Question: Passage: The San Diego Symphony at Symphony Towers performs on a regular basis and is directed by Jahja Ling. The San Diego Opera at Civic Center Plaza, directed by Ian Campbell, was ranked by Opera America as one of the top 10 opera companies in the United States. Old Globe Theatre at Balboa Park produces about 15 plays and musicals annually. The La Jolla Playhouse at UCSD is directed by Christopher Ashley. Both the Old Globe Theatre and the La Jolla Playhouse have produced the world premieres of plays and musicals that have gone on to win Tony Awards or nominations on Broadway. The Joan B. Kroc Theatre at Kroc Center's Performing Arts Center is a 600-seat state-of-the-art theatre that hosts music, dance, and theatre performances. The San Diego Repertory Theatre at the Lyceum Theatres in Horton Plaza produces a variety of plays and musicals. Hundreds of movies and a dozen TV shows have been filmed in San Diego, a tradition going back as far as 1898.

Answer: Who is the director of the San Francisco Symphony? 


Question: Passage: When Estonia was invaded and occupied by the Soviet Union in World War II, the status of the Estonian language changed to the first of two official languages (Russian being the other one). As with Latvia many immigrants entered Estonia under Soviet encouragement. In the second half of the 1970s, the pressure of bilingualism (for Estonians) intensified, resulting in widespread knowledge of Russian throughout the country. The Russian language was termed as ‘the language of friendship of nations’ and was taught to Estonian children, sometimes as early as in kindergarten. Although teaching Estonian to non-Estonians in schools was compulsory, in practice learning the language was often considered unnecessary.

Answer: What country did not occupy Estonia? 


Question: Passage: Between Bingen and Bonn, the Middle Rhine flows through the Rhine Gorge, a formation which was created by erosion. The rate of erosion equaled the uplift in the region, such that the river was left at about its original level while the surrounding lands raised. The gorge is quite deep and is the stretch of the river which is known for its many castles and vineyards. It is a UNESCO World Heritage Site (2002) and known as "the Romantic Rhine", with more than 40 castles and fortresses from the Middle Ages and many quaint and lovely country villages.

Answer:
In what year was "the Romantic Rhine" site built?