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What are ways to compare the “costs” and “gains” of food production systems?
I'm looking for methodologies to compare the costs a food production requires with the gains it delivers (not in economic terms).
I'm aware of energy returned on investment. Are there other methods ...
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Why does strenous exercise cause vision of “lights”?
I had a hard climb a week ago. I got so tired then any time I closed my eyes I saw these lights inside my head. I see these lights almost every time that I run fast or some thing like that. What are ...
