The problem: Answer a question about this article:
On the other hand, changes through the Phanerozoic correlate much better with the hyperbolic model (widely used in population biology, demography and macrosociology, as well as fossil biodiversity) than with exponential and logistic models. The latter models imply that changes in diversity are guided by a first-order positive feedback (more ancestors, more descendants) and/or a negative feedback arising from resource limitation. Hyperbolic model implies a second-order positive feedback. The hyperbolic pattern of the world population growth arises from a second-order positive feedback between the population size and the rate of technological growth. The hyperbolic character of biodiversity growth can be similarly accounted for by a feedback between diversity and community structure complexity. The similarity between the curves of biodiversity and human population probably comes from the fact that both are derived from the interference of the hyperbolic trend with cyclical and stochastic dynamics.
What models imply that changes in diversity are guided by a first-order positive feedback?
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The answer: exponential and logistic models


The problem: Answer a question about this article:
The largest and bloodiest American battle came at Okinawa, as the U.S. sought airbases for 3,000 B-29 bombers and 240 squadrons of B-17 bombers for the intense bombardment of Japan's home islands in preparation for a full-scale invasion in late 1945. The Japanese, with 115,000 troops augmented by thousands of civilians on the heavily populated island, did not resist on the beaches—their strategy was to maximize the number of soldier and Marine casualties, and naval losses from Kamikaze attacks. After an intense bombardment the Americans landed on 1 April 1945 and declared victory on 21 June. The supporting naval forces were the targets for 4,000 sorties, many by Kamikaze suicide planes. U.S. losses totaled 38 ships of all types sunk and 368 damaged with 4,900 sailors killed. The Americans suffered 75,000 casualties on the ground; 94% of the Japanese soldiers died along with many civilians.
How many Japanese troops were on Okinawa?
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The answer: 115,000


The problem: Answer a question about this article:
The brains of vertebrates are made of very soft tissue. Living brain tissue is pinkish on the outside and mostly white on the inside, with subtle variations in color. Vertebrate brains are surrounded by a system of connective tissue membranes called meninges that separate the skull from the brain. Blood vessels enter the central nervous system through holes in the meningeal layers. The cells in the blood vessel walls are joined tightly to one another, forming the blood–brain barrier, which blocks the passage of many toxins and pathogens (though at the same time blocking antibodies and some drugs, thereby presenting special challenges in treatment of diseases of the brain).
The blood-brain barrier is made up of what?
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The answer: cells in the blood vessel walls


The problem: Answer a question about this article:
The ability of the Dominions to set their own foreign policy, independent of Britain, was recognised at the 1923 Imperial Conference. Britain's request for military assistance from the Dominions at the outbreak of the Chanak Crisis the previous year had been turned down by Canada and South Africa, and Canada had refused to be bound by the 1923 Treaty of Lausanne. After pressure from Ireland and South Africa, the 1926 Imperial Conference issued the Balfour Declaration, declaring the Dominions to be "autonomous Communities within the British Empire, equal in status, in no way subordinate one to another" within a "British Commonwealth of Nations". This declaration was given legal substance under the 1931 Statute of Westminster. The parliaments of Canada, Australia, New Zealand, the Union of South Africa, the Irish Free State and Newfoundland were now independent of British legislative control, they could nullify British laws and Britain could no longer pass laws for them without their consent. Newfoundland reverted to colonial status in 1933, suffering from financial difficulties during the Great Depression. Ireland distanced itself further from Britain with the introduction of a new constitution in 1937, making it a republic in all but name.
When was the right of Dominions to determine their own foreign policy recognized?
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The answer:
1923