Problem: Mesozoic:

The Early Jurassic spans from 200 million years to 175 million years ago. The climate was much more humid than the Triassic, and as a result, the world was very tropical. In the oceans, Plesiosaurs, Ichthyosaurs and Ammonites fill waters as the dominant races of the seas. On land, dinosaurs and other reptiles stake their claim as the dominant race of the land, with species such as Dilophosaurus at the top. The first true crocodiles evolved, pushing out the large amphibians to near extinction. All-in-all, reptiles rise to rule the world. Meanwhile, the first true mammals evolve, but remained relatively small sized.

What feature of the climate produced a more tropical world?
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A: more humid


Problem: Energy:

Some types of energy are a varying mix of both potential and kinetic energy. An example is mechanical energy which is the sum of (usually macroscopic) kinetic and potential energy in a system. Elastic energy in materials is also dependent upon electrical potential energy (among atoms and molecules), as is chemical energy, which is stored and released from a reservoir of electrical potential energy between electrons, and the molecules or atomic nuclei that attract them.[need quotation to verify].The list is also not necessarily complete. Whenever physical scientists discover that a certain phenomenon appears to violate the law of energy conservation, new forms are typically added that account for the discrepancy.

All types of energy are a varying mix of potential and what other kind of energy?
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A: unanswerable


Problem: Diarrhea:

Basic sanitation techniques can have a profound effect on the transmission of diarrheal disease. The implementation of hand washing using soap and water, for example, has been experimentally shown to reduce the incidence of disease by approximately 42–48%. Hand washing in developing countries, however, is compromised by poverty as acknowledged by the CDC: "Handwashing is integral to disease prevention in all parts of the world; however, access to soap and water is limited in a number of less developed countries. This lack of access is one of many challenges to proper hygiene in less developed countries." Solutions to this barrier require the implementation of educational programs that encourage sanitary behaviours.

What is a solution to poverty?
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A: unanswerable


Problem: Middle Ages:

In agriculture, the increased usage of sheep with long-fibred wool allowed a stronger thread to be spun. In addition, the spinning wheel replaced the traditional distaff for spinning wool, tripling production.[AI] A less technological refinement that still greatly affected daily life was the use of buttons as closures for garments, which allowed for better fitting without having to lace clothing on the wearer. Windmills were refined with the creation of the tower mill, allowing the upper part of the windmill to be spun around to face the direction from which the wind was blowing. The blast furnace appeared around 1350 in Sweden, increasing the quantity of iron produced and improving its quality. The first patent law in 1447 in Venice protected the rights of inventors to their inventions.

What invention replaced laces on clothing?
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A:
buttons