Problem: Symbiosis:

A large percentage of herbivores have mutualistic gut flora that help them digest plant matter, which is more difficult to digest than animal prey. This gut flora is made up of cellulose-digesting protozoans or bacteria living in the herbivores' intestines. Coral reefs are the result of mutualisms between coral organisms and various types of algae that live inside them. Most land plants and land ecosystems rely on mutualisms between the plants, which fix carbon from the air, and mycorrhyzal fungi, which help in extracting water and minerals from the ground.

How do plants contribute to terrestrial ecosystems?
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A: fix carbon from the air


Problem: On the other hand, Belgian federalism is federated with three components. An affirmative resolution concerning Brussels' place in the federal system passed in the parliaments of Wallonia and Brussels. These resolutions passed against the desires of Dutch-speaking parties, who are generally in favour of a federal system with two components (i.e. the Dutch and French Communities of Belgium). However, the Flemish representatives in the Parliament of the Brussels Capital-Region voted in favour of the Brussels resolution, with the exception of one party. The chairman of the Walloon Parliament stated on July 17, 2008 that, "Brussels would take an attitude". Brussels' parliament passed the resolution on July 18, 2008:
What is Belgian Federalism? 
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Answer: the federal system passed in the parliaments of Wallonia and Brussels.


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
DNA replication is for the most part extremely accurate, however errors (mutations) do occur.:7.6 The error rate in eukaryotic cells can be as low as 10−8 per nucleotide per replication, whereas for some RNA viruses it can be as high as 10−3. This means that each generation, each human genome accumulates 1–2 new mutations. Small mutations can be caused by DNA replication and the aftermath of DNA damage and include point mutations in which a single base is altered and frameshift mutations in which a single base is inserted or deleted. Either of these mutations can change the gene by missense (change a codon to encode a different amino acid) or nonsense (a premature stop codon). Larger mutations can be caused by errors in recombination to cause chromosomal abnormalities including the duplication, deletion, rearrangement or inversion of large sections of a chromosome. Additionally, the DNA repair mechanisms that normally revert mutations can introduce errors when repairing the physical damage to the molecule is more important than restoring an exact copy, for example when repairing double-strand breaks.:5.4
What can small mutations be caused by?
A: DNA replication


Context and question: In 1931, RCA Victor introduced their vinyl-based Victrolac compound as a material for some unusual-format and special-purpose records. By the end of the 1930s vinyl's advantages of light weight, relative unbreakability and low surface noise had made it the material of choice for prerecorded radio programming and other critical applications. When it came to ordinary 78 rpm records, however, the much higher cost of the raw material, as well as its vulnerability to the heavy pickups and crudely mass-produced steel needles still commonly used in home record players, made its general substitution for shellac impractical at that time. During the Second World War, the United States Armed Forces produced thousands of 12-inch vinyl 78 rpm V-Discs for use by the troops overseas. After the war, the wider use of vinyl became more practical as new record players with relatively lightweight crystal pickups and precision-ground styli made of sapphire or an exotic osmium alloy proliferated. In late 1945, RCA Victor began offering special transparent red vinyl De Luxe pressings of some classical 78s, at a de luxe price. Later, Decca Records introduced vinyl Deccalite 78s, while other record companies came up with vinyl concoctions such as Metrolite, Merco Plastic and Sav-o-flex, but these were mainly used to produce "unbreakable" children's records and special thin vinyl DJ pressings for shipment to radio stations.
What was Metrolite and Sav-o-flex materials primarily used for?
Answer: children's records


Question: Oklahoma is in the nation's middle percentile in per capita spending on the arts, ranking 17th, and contains more than 300 museums. The Philbrook Museum of Tulsa is considered one of the top 50 fine art museums in the United States, and the Sam Noble Oklahoma Museum of Natural History in Norman, one of the largest university-based art and history museums in the country, documents the natural history of the region. The collections of Thomas Gilcrease are housed in the Gilcrease Museum of Tulsa, which also holds the world's largest, most comprehensive collection of art and artifacts of the American West.
Is there an answer to this question: What kind of museum is the Philbrook?

Answer: fine art


Question: In the US, African Americans, who include multiracial people, earn 75% of what white people earn. In Brazil, people of color earn less than 50% of what whites earn. Some have posited that the facts of lower socioeconomic status for people of color suggest that Brazil practices a kind of one-drop rule, or discrimination against people who are not visibly European in ancestry. The gap in income between blacks and other non-whites is relatively small compared to the large gap between whites and all people of color. Other social factors, such as illiteracy and education levels, show the same patterns of disadvantage for people of color. Some commentators observe that the United States practice of segregation and white supremacy in the South, and discrimination in many areas outside that region, forced many African Americans to unite in the civil rights struggle. They suggest that the fluid nature of race in Brazil has divided individuals of African descent, between those with more or less ancestry. As a result, they have not united for a stronger civil rights movement.[citation needed]
Is there an answer to this question: In the US, how much of what white people earn, do blacks earn?

Answer:
75%