The problem: Answer a question about this article:
During the Cenozoic era, specifically about 25 million years ago during the Miocene and Pliocene epochs, the continental climate became favorable to the evolution of grasslands. Existing forest biomes declined and grasslands became much more widespread. The grasslands provided a new niche for mammals, including many ungulates and glires, that switched from browsing diets to grazing diets. Traditionally, the spread of grasslands and the development of grazers have been strongly linked. However, an examination of mammalian teeth suggests that it is the open, gritty habitat and not the grass itself which is linked to diet changes in mammals, giving rise to the "grit, not grass" hypothesis.
the spread of grasslands and what have been strongly linked?
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The answer: development of grazers

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Wood, in the strict sense, is yielded by trees, which increase in diameter by the formation, between the existing wood and the inner bark, of new woody layers which envelop the entire stem, living branches, and roots. This process is known as secondary growth; it is the result of cell division in the vascular cambium, a lateral meristem, and subsequent expansion of the new cells. Where there are clear seasons, growth can occur in a discrete annual or seasonal pattern, leading to growth rings; these can usually be most clearly seen on the end of a log, but are also visible on the other surfaces. If these seasons are annual these growth rings are referred to as annual rings. Where there is no seasonal difference growth rings are likely to be indistinct or absent.
What is the process of trees growing out to get bigger around called?
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The answer: secondary growth

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After the American Revolutionary War, the number and proportion of free people of color increased markedly in the North and the South as slaves were freed. Most northern states abolished slavery, sometimes, like New York, in programs of gradual emancipation that took more than two decades to be completed. The last slaves in New York were not freed until 1827. In connection with the Second Great Awakening, Quaker and Methodist preachers in the South urged slaveholders to free their slaves. Revolutionary ideals led many men to free their slaves, some by deed and others by will, so that from 1782 to 1810, the percentage of free people of color rose from less than one percent to nearly 10 percent of blacks in the South.
How were the laws in New York abolished?
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The answer: in programs of gradual emancipation

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Iran has a paramilitary, volunteer militia force within the IRGC, called the Basij, which includes about 90,000 full-time, active-duty uniformed members. Up to 11 million men and women are members of the Basij who could potentially be called up for service; GlobalSecurity.org estimates Iran could mobilize "up to one million men". This would be among the largest troop mobilizations in the world. In 2007, Iran's military spending represented 2.6% of the GDP or $102 per capita, the lowest figure of the Persian Gulf nations. Iran's military doctrine is based on deterrence. In 2014 arms spending the country spent $15 billion and was outspent by the states of the Gulf Cooperation Council by a factor of 13.
In 2007 what was Iran spending 2.6% of its GDP on?
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The answer:
military spending