The Sun is the primary source of energy for ecosystems. The Sun emits . When an organism obtains nutrients by feeding on other organisms in the ecosystem, energy is used and released. Energy changes form, but it isn’t destroyed as it transforms. This scientific law is called the law of
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the national environmental policy act (nepa) is a united states environmental law that promotes the enhancement of the environment and established the president's council on environmental quality (ceq). the law was enacted on january 1, 1970. to date, more than 100 nations around the world have enacted national environmental policies modeled after nepa.

d. planting trees

the trees take in carbon to make oxygen.