Problem: 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.
What became more intense in the early 1970's in Estonia?
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Answer: unanswerable

Problem: On 15 August 2006, Brian May confirmed through his website and fan club that Queen + Paul Rodgers would begin producing their first studio album beginning in October, to be recorded at a "secret location". Queen + Paul Rodgers performed at the Nelson Mandela 90th Birthday Tribute held in Hyde Park, London on 27 June 2008, to commemorate Mandela's ninetieth birthday, and again promote awareness of the HIV/AIDS pandemic. The first Queen + Paul Rodgers album, titled The Cosmos Rocks, was released in Europe on 12 September 2008 and in the United States on 28 October 2008. Following the release of the album, the band again went on a tour through Europe, opening on Kharkiv's Freedom Square in front of 350,000 Ukrainian fans. The Kharkiv concert was later released on DVD. The tour then moved to Russia, and the band performed two sold-out shows at the Moscow Arena. Having completed the first leg of its extensive European tour, which saw the band play 15 sold-out dates across nine countries, the UK leg of the tour sold out within 90 minutes of going on sale and included three London dates, the first of which was The O2 on 13 October. The last leg of the tour took place in South America, and included a sold-out concert at the Estadio Jose Amalfitani, Buenos Aires.
What was the name of Queen + Paul Rodgers debut album?
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Answer: The Cosmos Rocks

Problem: A state's consent may be invalidated if there was an erroneous understanding of a fact or situation at the time of conclusion, which formed the "essential basis" of the state's consent. Consent will not be invalidated if the misunderstanding was due to the state's own conduct, or if the truth should have been evident.
What, if it formed the "essential basis" of a state's consent to a treaty, may invalidate that consent?
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Answer:
an erroneous understanding of a fact or situation