The document is a practice exam for an Environmental Chemical Analysis and Control course. It contains 30 multiple choice questions testing knowledge of various topics related to air pollution and chemical analysis techniques. Specifically, it covers the causes and effects of air pollution, greenhouse gases, sampling methods, digestion/dissolution techniques, analysis methods for sulfur dioxide, nitrogen dioxide, chlorinated pesticides, and cyanide, and principles of techniques like polarography, potentiometry, and amperometry.