Problem: Tristan da Cunha:

On 16 March 2011, the freighter MS Oliva ran aground on Nightingale Island, spilling tons of heavy fuel oil into the ocean, leaving an oil slick threatening the island's population of rockhopper penguins. Nightingale Island has no fresh water, so the penguins were transported to Tristan da Cunha for cleaning.

When did MS Oliva spill Tristan da Cunha into the ocean?
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A: unanswerable

Problem: Data compression:

Video data may be represented as a series of still image frames. The sequence of frames contains spatial and temporal redundancy that video compression algorithms attempt to eliminate or code in a smaller size. Similarities can be encoded by only storing differences between frames, or by using perceptual features of human vision. For example, small differences in color are more difficult to perceive than are changes in brightness. Compression algorithms can average a color across these similar areas to reduce space, in a manner similar to those used in JPEG image compression. Some of these methods are inherently lossy while others may preserve all relevant information from the original, uncompressed video.

What is hard to tell with smaller differences involved?
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A: color

Problem: Marshall Islands:

The Spanish ship San Pedro and two other vessels in an expedition commanded by Miguel Lopez de Legazpi discovered an island on January 9, 1530, possibly Mejit, at 10N, which they named "Los Barbudos". The Spaniards went ashore and traded with the local inhabitants. On January 10, the Spaniards sighted another island that they named "Placeres", perhaps Ailuk; ten leagues away, they sighted another island that they called "Pajares" (perhaps Jemo). On January 12, they sighted another island at 10N that they called "Corrales" (possibly Wotho). On January 15, the Spaniards sighted another low island, perhaps Ujelang, at 10N, where they described the people on "Barbudos". After that, ships including the San Jeronimo, Los Reyes and Todos los Santos also visited the islands in different years.

On what date did Legazpi's expedition see the island it named Placeres?
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A: January 10

Problem: Russian language:

According to the Institute of Russian Language of the Russian Academy of Sciences, an optional acute accent ( ) may, and sometimes should, be used to mark stress. For example, it is used to distinguish between otherwise identical words, especially when context does not make it obvious: / (lock/castle), / (worthwhile/standing), / (this is odd/this is marvelous), / (attaboy/fine young man), / (I shall learn it/I recognize it), / (to be cutting/to have cut); to indicate the proper pronunciation of uncommon words, especially personal and family names (, , , , ), and to show which is the stressed word in a sentence ( ?/ ?/ ? Was it you who ate the cookie?/Did you eat the cookie?/Was it the cookie that you ate?). Stress marks are mandatory in lexical dictionaries and books for children or Russian learners.

What should be used to teach Russian learners according to the Russian Academy of Sciences?
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A:
unanswerable