Nitrogen fixation is carried out primarily by a. plants b. humans c. consumers d. bacteria

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Achild is suffering from fever but the doctor cannot immediately pinpoint the alignment on the basis of this one symptom explain why also mention other two such general symptoms

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of