Explain why antarctic circle have 24 hours of darkness at june 21st...

This is because the earth is tilted at a 23.5 degree angle, and during the winter solstice, the southern hemisphere is tilted away from the Sun, meaning that the antarctic circle is completely tilted away from the Sun, hence it experiences 24 hour nighttime

Explanation:

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d. stage 4

explanation:

the existence of some kind of demographic transition is widely accepted in the social sciences because of the well-established historical correlation linking dropping fertility to social and economic development.[1] scholars debate whether industrialization and higher incomes lead to lower population, or whether lower populations lead to industrialization and higher incomes. scholars also debate to what extent various proposed and sometimes inter-related factors such as higher per capita income,lower mortality, old-age security, and rise of demand for human capital are involved.[2]