Problem: He notes that both A. P. de Candolle and Charles Lyell had stated that all organisms are exposed to severe competition. Darwin emphasizes that he used the phrase "struggle for existence" in "a large and metaphorical sense, including dependence of one being on another"; he gives examples ranging from plants struggling against drought to plants competing for birds to eat their fruit and disseminate their seeds. He describes the struggle resulting from population growth: "It is the doctrine of Malthus applied with manifold force to the whole animal and vegetable kingdoms." He discusses checks to such increase including complex ecological interdependencies, and notes that competition is most severe between closely related forms "which fill nearly the same place in the economy of nature".
When is competition strongest in the natural world?
The answer is the following: competition is most severe between closely related forms

Problem: Many components of the immune system are typically cellular in nature and not associated with any specific organ; but rather are embedded or circulating in various tissues located throughout the body.
Are immune tissues typically fixed with specific organs usually?
The answer is the following: not associated with any specific organ

Problem: For the past 25 years, the Tucson Folk Festival has taken place the first Saturday and Sunday of May in downtown Tucson's El Presidio Park. In addition to nationally known headline acts each evening, the Festival highlights over 100 local and regional musicians on five stages is one of the largest free festivals in the country. All stages are within easy walking distance. Organized by the Tucson Kitchen Musicians Association, volunteers make this festival possible. KXCI 91.3-FM, Arizona's only community radio station, is a major partner, broadcasting from the Plaza Stage throughout the weekend. In addition, there are numerous workshops, events for children, sing-alongs, and a popular singer/songwriter contest. Musicians typically play 30-minute sets, supported by professional audio staff volunteers. A variety of food and crafts are available at the festival, as well as local micro-brews. All proceeds from sales go to fund future festivals.
How much does the Tucson Folk Festival cost to get in?
The answer is the following: free

Problem: On 12 January 1953, he was appointed Patriarch of Venice and, accordingly, raised to the rank of Cardinal-Priest of Santa Prisca by Pope Pius XII. Roncalli left France for Venice on 23 February 1953 stopping briefly in Milan and then to Rome. On 15 March 1953, he took possession of his new diocese in Venice. As a sign of his esteem, the President of France, Vincent Auriol, claimed the ancient privilege possessed by French monarchs and bestowed the red biretta on Roncalli at a ceremony in the Elysee Palace. It was around this time that he, with the aid of Monsignor Bruno Heim, formed his coat of arms with a lion of Saint Mark on a white ground. Auriol also awarded Roncalli three months later with the award of Commander of the Legion of Honour.
When did he take up his new diocese in Venice?
The answer is the following:
15 March 1953