Problem: Gramophone record:

Vinyl pressings were made with stampers from master cuts that were electroplated in vacuo by means of gold sputtering. Audio response was claimed out to 8,000 Hz, later 13,000 Hz, using light weight pickups employing jeweled styli. Amplifiers and cutters both using negative feedback were employed thereby improving the range of frequencies cut and lowering distortion levels. Radio transcription producers such as World Broadcasting System and Associated Music Publishers (AMP) were the dominant licensees of the Western Electric wide range system and towards the end of the 1930s were responsible for two-thirds of the total radio transcription business. These recordings use a bass turnover of 300 Hz and a 10,000 Hz rolloff of 8.5 dB.

How was gold spluttering used in vinyl creation?
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A: cuts that were electroplated in vacuo by means of gold sputtering

Problem: Geological history of Earth:

A global drop in sea level at the end of the Devonian reversed early in the Carboniferous; this created the widespread epicontinental seas and carbonate deposition of the Mississippian. There was also a drop in south polar temperatures; southern Gondwana was glaciated throughout the period, though it is uncertain if the ice sheets were a holdover from the Devonian or not. These conditions apparently had little effect in the deep tropics, where lush coal swamps flourished within 30 degrees of the northernmost glaciers. A mid-Carboniferous drop in sea-level precipitated a major marine extinction, one that hit crinoids and ammonites especially hard. This sea-level drop and the associated unconformity in North America separate the Mississippian Period from the Pennsylvanian period.

What temperatures dropped during the Devonian?
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A: unanswerable

Problem: Hellenistic period:

Hellenistic poets now sought patronage from kings, and wrote works in their honor. The scholars at the libraries in Alexandria and Pergamon focused on the collection, cataloging, and literary criticism of classical Athenian works and ancient Greek myths. The poet-critic Callimachus, a staunch elitist, wrote hymns equating Ptolemy II to Zeus and Apollo. He promoted short poetic forms such as the epigram, epyllion and the iambic and attacked epic as base and common ("big book, big evil" was his doctrine). He also wrote a massive catalog of the holdings of the library of Alexandria, the famous Pinakes. Callimachus was extremely influential in his time and also for the development of Augustan poetry. Another poet, Apollonius of Rhodes, attempted to revive the epic for the Hellenistic world with his Argonautica. He had been a student of Callimachus and later became chief librarian (prostates) of the library of Alexandria, Apollonius and Callimachus spent much of their careers feuding with each other. Pastoral poetry also thrived during the Hellenistic era, Theocritus was a major poet who popularized the genre.

Who wrote hymns equating Ptolemy II to Zeus and Apollo?
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A: Callimachus

Problem: Pacific War:

The battle secured the beachheads of the U.S. Sixth Army on Leyte against attack from the sea, broke the back of Japanese naval power and opened the way for an advance to the Ryukyu Islands in 1945. The only significant Japanese naval operation afterwards was the disastrous Operation Ten-Go in April 1945. Kurita's force had begun the battle with five battleships; when he returned to Japan, only Yamato was combat-worthy. Nishimura's sunken Yamashiro was the last battleship in history to engage another in combat.

When did Operation Ten-Go occur?
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A:
April 1945