41 Arranging and conducting of colloquiums, conferences, seminars in the fields of aeronautics, space exploration, energy conservation, aircraft propulsion, engine development, environmental preservation, avionics, telecommunications, navigation, civil engineering and mechanical engineering; arranging educational and entertainment competitions in the fields of aeronautics, space exploration, energy conservation, aircraft propulsion, engine development, environmental preservation, avionics, telecommunications, navigation, civil engineering and mechanical engineering; organization of exhibitions for cultural or educational purposes in the fields of aeronautics, space exploration, energy conservation, aircraft propulsion, engine development, environmental preservation, avionics, telecommunications, navigation, civil engineering and mechanical engineering; education services, namely, correspondence courses in the fields of aeronautics, space exploration, energy conservation, aircraft propulsion, engine development, environmental preservation, avionics, telecommunications, navigation, civil engineering and mechanical engineering; practical training in the fields of aeronautics, space exploration, energy conservation, aircraft propulsion, engine development, environmental preservation, avionics, telecommunications, navigation, civil engineering and mechanical engineering; providing education information in the fields of aeronautics, space exploration, energy conservation, aircraft propulsion, engine development, environmental preservation, avionics, telecommunications, navigation, civil engineering and mechanical engineering; digital imaging services; videotaping; rental of videotapes; videotape film production; and publication of books, journals, newspapers, magazines, all in the fields of aeronautics, space exploration, energy conservation, aircraft propulsion, engine development, environmental preservation, avionics, telecommunications, navigation, civil engineering and mechanical engineering