Problem: Adult contemporary music:

Adult contemporary traces its roots to the 1960s easy listening format, which adopted a 70-80% instrumental - 20-30% vocal mix. A few offered 90% instrumentals, and a handful were entirely instrumental. The easy listening format, as it was first known, was born of a desire by some radio stations in the late 1950s and early 1960s to continue playing current hit songs but distinguish themselves from being branded as "rock and roll" stations. Billboard first published the Easy Listening chart July 17, 1961, with 20 songs; the first number one was "Boll Weevil Song" by Brook Benton. The chart described itself as "not too far out in either direction".

Generally speaking, what percentage of music on easy listening stations was instrumental?
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A: 70-80%

Problem: Unicode:

In 1996, a surrogate character mechanism was implemented in Unicode 2.0, so that Unicode was no longer restricted to 16 bits. This increased the Unicode codespace to over a million code points, which allowed for the encoding of many historic scripts (e.g., Egyptian Hieroglyphs) and thousands of rarely used or obsolete characters that had not been anticipated as needing encoding. Among the characters not originally intended for Unicode are rarely used Kanji or Chinese characters, many of which are part of personal and place names, making them rarely used, but much more essential than envisioned in the original architecture of Unicode.

What are the extra Unicode characters called?
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A: unanswerable

Problem: Architecture:

In Renaissance Europe, from about 1400 onwards, there was a revival of Classical learning accompanied by the development of Renaissance Humanism which placed greater emphasis on the role of the individual in society than had been the case during the Medieval period. Buildings were ascribed to specific architects Brunelleschi, Alberti, Michelangelo, Palladio and the cult of the individual had begun. There was still no dividing line between artist, architect and engineer, or any of the related vocations, and the appellation was often one of regional preference.

What was developed before 1400?
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A: unanswerable

Problem: Capacitor:

When there is a potential difference across the conductors (e.g., when a capacitor is attached across a battery), an electric field develops across the dielectric, causing positive charge +Q to collect on one plate and negative charge Q to collect on the other plate. If a battery has been attached to a capacitor for a sufficient amount of time, no current can flow through the capacitor. However, if a time-varying voltage is applied across the leads of the capacitor, a displacement current can flow.

What happens to the current when a battery has been attached to a capacitor for an adequate amount of time?
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A:
no current can flow through the capacitor