Answer:
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Explanation:
Similarly, a day with a mean temperature below 20° F is associated with an increase in annual mortality of roughly 0.07–0.08 percent. ... The preferred estimates suggest that climate change will lead to an increase in the age adjusted U.S. mortality rate of 3 percent by the end of the twenty-first century.
The answer is: nature and nurture
Nature and nurture is the ongoing debate in psychological field on whether humans development is mostly influenced by environmental or genetic factors.
Twins often used in such experiment because they have same genetic material. This means that if they were separated, the researchers could analyze whether the environment where they grow up resulted in radical difference within the children's development.