Input: Read this: A "tag" in an audio file is a section of the file that contains metadata such as the title, artist, album, track number or other information about the file's contents. The MP3 standards do not define tag formats for MP3 files, nor is there a standard container format that would support metadata and obviate the need for tags.
Question: What do MP3 standards not define?

Output: tag formats for MP3 files

QUES: Hops contain several characteristics that brewers desire in beer. Hops contribute a bitterness that balances the sweetness of the malt; the bitterness of beers is measured on the International Bitterness Units scale. Hops contribute floral, citrus, and herbal aromas and flavours to beer. Hops have an antibiotic effect that favours the activity of brewer's yeast over less desirable microorganisms and aids in "head retention", the length of time that a foamy head created by carbonation will last. The acidity of hops is a preservative.

What is the main cause for the bitterness in beer?
What is the answer?
ANS: Hops

QUES: Presbyterian denominations that trace their heritage to the British Isles usually organise their church services inspired by the principles in the Directory of Public Worship, developed by the Westminster Assembly in the 1640s. This directory documented Reformed worship practices and theology adopted and developed over the preceding century by British Puritans, initially guided by John Calvin and John Knox. It was enacted as law by the Scottish Parliament, and became one of the foundational documents of Presbyterian church legislation elsewhere.
Which denomination's heritage can be traced to John Calvin?

ANS: unanswerable

Men's rhythmic gymnastics is related to both Men's artistic gymnastics and wushu martial arts. It emerged in Japan from stick gymnastics. Stick gymnastics has been taught and performed for many years with the aim of improving physical strength and health. Male athletes are judged on some of the same physical abilities and skills as their female counterparts, such as hand/body-eye co-ordination, but tumbling, strength, power, and martial arts skills are the main focus, as opposed to flexibility and dance in women's rhythmic gymnastics. There are a growing number of participants, competing alone and on a team; it is most popular in Asia, especially in Japan where high school and university teams compete fiercely. As of 2002[update], there were 1000 men's rhythmic gymnasts in Japan.[citation needed]
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Why do people in Japan eat a diet high in fiber?
Ah, so.. unanswerable

Question: The most-commonly accepted theory is that these events were triggered by the onset of an ice age, in the Hirnantian faunal stage that ended the long, stable greenhouse conditions typical of the Ordovician. The ice age was probably not as long-lasting as once thought; study of oxygen isotopes in fossil brachiopods shows that it was probably no longer than 0.5 to 1.5 million years. The event was preceded by a fall in atmospheric carbon dioxide (from 7000ppm to 4400ppm) which selectively affected the shallow seas where most organisms lived. As the southern supercontinent Gondwana drifted over the South Pole, ice caps formed on it. Evidence of these ice caps have been detected in Upper Ordovician rock strata of North Africa and then-adjacent northeastern South America, which were south-polar locations at the time.
Try to answer this question if possible: What showed that the ice age lasted longer than originally thought?
Answer: unanswerable

Problem: Technologies based upon the polymerase chain reaction (PCR) method will become nearly ubiquitous gold standards of diagnostics of the near future, for several reasons. First, the catalog of infectious agents has grown to the point that virtually all of the significant infectious agents of the human population have been identified. Second, an infectious agent must grow within the human body to cause disease; essentially it must amplify its own nucleic acids in order to cause a disease. This amplification of nucleic acid in infected tissue offers an opportunity to detect the infectious agent by using PCR. Third, the essential tools for directing PCR, primers, are derived from the genomes of infectious agents, and with time those genomes will be known, if they are not already.
What does the acronym PCR abbreviate to?
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Answer:
unanswerable