• 4 Videos, Slides, Films

• 2 Air
• 2 Climatic changes
• 2 Global warming
• 2 History
• 2 Technological innovations
• 2 Technology
• 2 Toxicology
• 2 Water
• 1 Agricultural education
• 1 Agronomy
• 1 Climate
• 1 Conservation of natural resources
• 1 Developing countries
• 1 Earth (Planet)
• 1 Earth movements
• 1 Earth sciences
• 1 Engineering
• 1 Environmental law
• 1 Environmental policy
• 1 Environmental protection
• 1 Geography
• 1 Geology
• 1 Industrial engineering

• 4 Infobase

• 4 English

• 4 Internet videos
• 3 Video recordings for the hearing impaired

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