Problem: Vacuum:

Historically, there has been much dispute over whether such a thing as a vacuum can exist. Ancient Greek philosophers debated the existence of a vacuum, or void, in the context of atomism, which posited void and atom as the fundamental explanatory elements of physics. Following Plato, even the abstract concept of a featureless void faced considerable skepticism: it could not be apprehended by the senses, it could not, itself, provide additional explanatory power beyond the physical volume with which it was commensurate and, by definition, it was quite literally nothing at all, which cannot rightly be said to exist. Aristotle believed that no void could occur naturally, because the denser surrounding material continuum would immediately fill any incipient rarity that might give rise to a void.

Aristotle thought what would fill any rarity that might give rise to a void?
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A: denser surrounding material continuum

Problem: Boston:

The area's many colleges and universities make Boston an international center of higher education and medicine, and the city is considered to be a world leader in innovation. Boston's economic base also includes finance, professional and business services, biotechnology, information technology, and government activities. Households in the city claim the highest average rate of philanthropy in the United States; businesses and institutions rank amongst the top in the country for environmental sustainability and investment. The city has one of the highest costs of living in the United States, though it remains high on world livability rankings.

Boston is internationally known for education and medicine because of its many what?
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A: colleges and universities

Problem: American Idol:

American Idol has traditionally released studio recordings of contestants' performances as well as the winner's coronation single for sale. For the first five seasons, the recordings were released as a compilation album at the end of the season. All five of these albums reached the top ten in Billboard 200 which made then American Idol the most successful soundtrack franchise of any motion picture or television program. Starting late in season five, individual performances were released during the season as digital downloads, initially from the American Idol official website only. In season seven the live performances and studio recordings were made available during the season from iTunes when it joined as a sponsor. In Season ten the weekly studio recordings were also released as compilation digital album straight after performance night.

When did iTunes become a sponsor on American Idol?
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A: season seven

Problem: Crimean War:

Russia feared losing Russian America without compensation in some future conflict, especially to the British. While Alaska attracted little interest at the time, the population of nearby British Columbia started to increase rapidly a few years after hostilities ended. Therefore, the Russian emperor, Alexander II, decided to sell Alaska. In 1859 the Russians offered to sell the territory to the United States, hoping that its presence in the region would offset the plans of Russia's greatest regional rival, the United Kingdom.

What did the Russians fear losing without compensation?
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A:
British Columbia