Problem: Great Plains:

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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A: development of grazers


Problem: Software testing:

A primary purpose of testing is to detect software failures so that defects may be discovered and corrected. Testing cannot establish that a product functions properly under all conditions but can only establish that it does not function properly under specific conditions. The scope of software testing often includes examination of code as well as execution of that code in various environments and conditions as well as examining the aspects of code: does it do what it is supposed to do and do what it needs to do. In the current culture of software development, a testing organization may be separate from the development team. There are various roles for testing team members. Information derived from software testing may be used to correct the process by which software is developed.

In the previous culture of software development, what two things were separate?
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A: unanswerable


Problem: Rajasthan:

Modern Rajasthan includes most of Rajputana, which comprises the erstwhile nineteen princely states, two chiefships, and the British district of Ajmer-Merwara. Marwar (Jodhpur), Bikaner, Mewar (Chittorgarh), Alwar and Dhundhar (Jaipur) were some of the main Rajput princely states. Bharatpur and Dholpur were Jat princely states whereas Tonk was a princely state under a Muslim Nawab. Rajput families rose to prominence in the 6th century CE. The Rajputs put up a valiant resistance to the Islamic invasions and protected this land with their warfare and chivalry for more than 500 years. They also resisted Mughal incursions into India and thus contributed to their slower-than-anticipated access to the Indian subcontinent. Later, the Mughals, through skilled warfare, were able to get a firm grip on northern India, including Rajasthan. Mewar led other kingdoms in its resistance to outside rule. Most notably, Rana Sanga fought the Battle of Khanua against Babur, the founder of the Mughal empire.

How many princely states of Rajputana contain?
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A: nineteen


Problem: Biodiversity:

The history of biodiversity during the Phanerozoic (the last 540 million years), starts with rapid growth during the Cambrian explosion—a period during which nearly every phylum of multicellular organisms first appeared. Over the next 400 million years or so, invertebrate diversity showed little overall trend, and vertebrate diversity shows an overall exponential trend. This dramatic rise in diversity was marked by periodic, massive losses of diversity classified as mass extinction events. A significant loss occurred when rainforests collapsed in the carboniferous. The worst was the Permian-Triassic extinction event, 251 million years ago. Vertebrates took 30 million years to recover from this event.

In which event did the vertebrates collapse in the carboniferous?
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A:
unanswerable