Question: How was it determined that Delaware County (the one that shares border with Chester County) has a population of 560699?
Choices:
Sixth National Population Census of the People's Republic of China
2000 United States Census
de facto
estimation process
UIS estimation
Census
United Kingdom Census 1971
Yemen General Census of Population, Housing and Establishments 2004
Family record booklet
Pensky–Martens closed-cup test