The problem: Answer a question about this article:
Many annual events celebrate the diverse cultures of Houston. The largest and longest running is the annual Houston Livestock Show and Rodeo, held over 20 days from early to late March, is the largest annual livestock show and rodeo in the world. Another large celebration is the annual night-time Houston Pride Parade, held at the end of June. Other annual events include the Houston Greek Festival, Art Car Parade, the Houston Auto Show, the Houston International Festival, and the Bayou City Art Festival, which is considered to be one of the top five art festivals in the United States.
Where does the Bayou City Art Festival rank in U.S. art festivals?
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The answer: one of the top five

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Samba Schools are large, social entities with thousands of members and a theme for their song and parade each year. In Rio Carnival, samba schoolsparade in the Sambadrome ("sambodromo" in Portuguese). Some of the most famous include GRES Estacao Primeira de Mangueira, GRES Portela, GRES Imperatriz Leopoldinense, GRES Beija-Flor de Nilopolis, GRES Mocidade Independente de Padre Miguel, and recently, Unidos da Tijuca and GRES Uniao da Ilha do Governador. Local tourists pay $500950, depending on the costume, to buy a Samba costume and dance in the parade. Blocos are small informal groups with a definite theme in their samba, usually satirizing the political situation. About 30 schools in Rio gather hundreds of thousands of participants. More than 440 blocos operate in Rio. Bandas are samba musical bands, also called "street carnival bands", usually formed within a single neighborhood or musical back-ground. The Carnival industry chain amassed in 2012 almost US$1 billion in revenues.
About how many Samba schools are in Rio?
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The answer: 30

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The strategy behind the formation of the Warsaw Pact was driven by the desire of the Soviet Union to dominate Central and Eastern Europe. This policy was driven by ideological and geostrategic reasons. Ideologically, the Soviet Union arrogated the right to define socialism and communism and act as the leader of the global socialist movement. A corollary to this idea was the necessity of intervention if a country appeared to be violating core socialist ideas and Communist Party functions, which was explicitly stated in the Brezhnev Doctrine. Geostrategic principles also drove the Soviet Union to prevent invasion of its territory by Western European powers.
Which Soviet leader formed doctrine aimed at keeping socialist satellite nations in line?
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The answer: Brezhnev

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Antibiotics are screened for any negative effects on humans or other mammals before approval for clinical use, and are usually considered safe and most are well tolerated. However, some antibiotics have been associated with a range of adverse side effects. Side-effects range from mild to very serious depending on the antibiotics used, the microbial organisms targeted, and the individual patient. Side effects may reflect the pharmacological or toxicological properties of the antibiotic or may involve hypersensitivity reactions or anaphylaxis. Safety profiles of newer drugs are often not as well established as for those that have a long history of use. Adverse effects range from fever and nausea to major allergic reactions, including photodermatitis and anaphylaxis. Common side-effects include diarrhea, resulting from disruption of the species composition in the intestinal flora, resulting, for example, in overgrowth of pathogenic bacteria, such as Clostridium difficile. Antibacterials can also affect the vaginal flora, and may lead to overgrowth of yeast species of the genus Candida in the vulvo-vaginal area. Additional side-effects can result from interaction with other drugs, such as elevated risk of tendon damage from administration of a quinolone antibiotic with a systemic corticosteroid. Some scientists have hypothesized that the indiscriminate use of antibiotics alter the host microbiota and this has been associated with chronic disease.
What causes diarrhea?
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The answer:
disruption of the species composition in the intestinal flora