Problem: A cappella:

While worship in the Temple in Jerusalem included musical instruments (2 Chronicles 29:2527), traditional Jewish religious services in the Synagogue, both before and after the last destruction of the Temple, did not include musical instruments given the practice of scriptural cantillation. The use of musical instruments is traditionally forbidden on the Sabbath out of concern that players would be tempted to repair (or tune) their instruments, which is forbidden on those days. (This prohibition has been relaxed in many Reform and some Conservative congregations.) Similarly, when Jewish families and larger groups sing traditional Sabbath songs known as zemirot outside the context of formal religious services, they usually do so a cappella, and Bar and Bat Mitzvah celebrations on the Sabbath sometimes feature entertainment by a cappella ensembles. During the Three Weeks musical instruments are prohibited. Many Jews consider a portion of the 49-day period of the counting of the omer between Passover and Shavuot to be a time of semi-mourning and instrumental music is not allowed during that time. This has led to a tradition of a cappella singing sometimes known as sefirah music.

How many days are counted between Passover and Shavuot?
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A: 49

Problem: Sanskrit:

Brahmi evolved into a multiplicity of Brahmic scripts, many of which were used to write Sanskrit. Roughly contemporary with the Brahmi, Kharosthi was used in the northwest of the subcontinent. Sometime between the fourth and eighth centuries, the Gupta script, derived from Brahmi, became prevalent. Around the eighth century, the Sarada script evolved out of the Gupta script. The latter was displaced in its turn by Devanagari in the 11th or 12th century, with intermediary stages such as the Siddham script. In East India, the Bengali alphabet, and, later, the Odia alphabet, were used.

What script evolved from the Gupta script?
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A: Sarada

Problem: MP3:

Unauthorized MP3 file sharing continues on next-generation peer-to-peer networks. Some authorized services, such as Beatport, Bleep, Juno Records, eMusic, Zune Marketplace, Walmart.com, Rhapsody, the recording industry approved re-incarnation of Napster, and Amazon.com sell unrestricted music in the MP3 format.

Which format is used by the companies that sell the music legally?
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A: MP3

Problem: Mesozoic:

The Early Jurassic spans from 200 million years to 175 million years ago. The climate was much more humid than the Triassic, and as a result, the world was very tropical. In the oceans, Plesiosaurs, Ichthyosaurs and Ammonites fill waters as the dominant races of the seas. On land, dinosaurs and other reptiles stake their claim as the dominant race of the land, with species such as Dilophosaurus at the top. The first true crocodiles evolved, pushing out the large amphibians to near extinction. All-in-all, reptiles rise to rule the world. Meanwhile, the first true mammals evolve, but remained relatively small sized.

What species saw itself at the bottom of the race hierarchy?
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A:
unanswerable