Ifeel like the answer is number 4 but im not sure. what was the key factor in creating the earth's early atmosphere? respiration of single-celled organisms photosynthesis of land plants violent storms outgassing by volcanoes

What is the 77 element on the periodtic table

An ecologist studied the same species of deer during the summer and the winter. she noticed that during the summer, when there was plenty of food, the deer were energetic and playful. however, during winter when food was scarce, the deer moved more slowly and did not run unless they needed to escape a predator. which scientific fact is best supported by her observations?

Which process in respiration happens first? a)pyruvate processing b)electron transport chain c)krebs cycle d)glycolysis