Answer:
For early earth, it was filled with loads of oxygen and could kill humans if they breathed the oxygen that was in the air about 100 million years ago. This massive amount of oxygen cause massive creatures like the dinosaurs to exist. Current earth has an atmosphere with not too much oxygen.
Explanation:
brainliest
Fungi and bacteria are primary decomposers whereas plants and trees are producers and animals are consumers
Answer:
a = 9
Explanation:
5(a + 4) - 6a + 1 = 12
5a + 20 - 6a + 1 = 12
5a - 6a + 20 + 1 = 12
-1a + 21 = 12
-21 -21
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-1a = -9
/-1 /-1
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a = 9
