What is the composition of the earth

At the center of the Earth is the core, which has two parts. The solid, inner core of iron has a radius of about 760 miles (about 1,220 km), according to NASA. It is surrounded by a liquid, outer core composed of a nickel-iron alloy.

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]

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