ผู้เขียน: Alexander J. Kunis

The involvement of insurgent and extremist groups in criminal activity is an issue that has been a concern of U.S. administrations for decades. In recent years, some observers have claimed that inter …

Particulate matter are fine particles, and soot, which are tiny subdivisions of solid matter suspended in a gas or liquid. Sources of particulate matter can be man-made or natural. Air pollution and …