Fig. 3.
Graphic representation of selected factors used in this study. Note that distance to the airport, borders, towns and mines were calculated using the Euclidean distance approach.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.