Examlex
Two stars both lie on the main sequence.Star X is spectral type A,while Star Y is spectral type G.Therefore,Star X is more massive than Star Y.
Environmental Sustainability
The practice of ensuring natural resources are used in a way that maintains their viability and preserves them for future generations.
Sustainable Development
Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
Deep Ecologists
An environmental movement and philosophy that regards human life as just one of many equal components of a global ecosystem.
Nonhierarchical Societies
Communities or societies that do not have a rigid system of hierarchy and do not typically operate under the principle of top-down leadership or authority structures.
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