• 45 Videos, Slides, Films

• 45 Energy consumption
• 45 Energy development
• 45 Environmental aspects
• 45 Natural resources
• 17 Conservation of natural resources
• 15 Environmental protection
• 9 Economic aspects
• 8 Water
• 7 Government policy
• 7 Human ecology
• 7 Study and teaching
• 6 Business ethics
• 6 Effect of human beings on
• 6 Land use
• 6 Moral and ethical aspects
• 6 Nature
• 6 Pollution
• 5 Ecosystem management
• 5 Geology, Structural
• 5 Human geography
• 5 Mantle
• 5 Physical geography
• 4 Air

• 45 Films Media Group
• 45 Films for the Humanities & Sciences (Firm)
• 7 Public Broadcasting Service (U.S.)
• 5 Infobase
• 5 Video Education Australasia
• 3 Allegro Productions (Firm)
• 3 Cambridge Educational (Firm)
• 2 ABC News Productions
• 2 Canadian Broadcasting Corporation
• 2 National Geographic Television & Film
• 1 4 Learning (Firm)
• 1 ABC International
• 1 Agency for Instructional Technology
• 1 Alda, Alan, 1936-
• 1 American Public Television
• 1 BBC Worldwide Ltd
• 1 Electric Sky (Firm)
• 1 Essay Films Ltd
• 1 Ethical Markets Media
• 1 Fred Friendly Seminars (Firm)
• 1 Galloping Pictures
• 1 Gliner, Robert
• 1 Information Television Network
• 1 Journeyman Pictures (Firm)
• 1 National Film Board of Canada

• 45 English
• 1 Multiple languages

• 5 Earth (Planet)
• 3 Middle East
• 3 United States
• 2 India
• 1 Asia
• 1 Brazil
• 1 California
• 1 Pacific Area
• 1 South Asia
• 1 United Arab Emirates

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