What concession did the United
States receive from north
Vietnam in the Paris peace
accords?

im pretty sure its none of them

all 4 come together due to gravity

all objects have gravity, even atoms

but their gravitational force is very low and it takes a long time for them to become closer together

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]