Air pollution is caused by the presence of (7) substances in the air, mainly produced by human activities, even though sometimes it can result from natural (8) such as volcanic eruption and dust storm

Why would nations in latin america be part of a mostly arab cartel group known as opec? a) latin america refused to do business with countries that were not part of opec. eliminate b) natural resources such as oil are a major economic development for some latin american countries. c) latin america has a long history of distrust of the united states and fears a take-over of oil fields. d) latin american nations such as venezuela needed in getting natural resources to other parts of the world. 15