Question

where is it thought the first life began on earth?
o a in the atmosphere
o b on land volcanoes
o c deep in the oceans near volcanic vents
o d on the surface of the moon
question 13 (1 point)
what major change did cyanobacteria bring to earth?
o a creation of the moon
o b oxygenation of the atmosphere
o c the first multicelled animals
o d the rise of mammals

Explanation:

It is widely thought that the first life on Earth began deep in the oceans near volcanic vents as these areas provided the necessary energy and chemical - rich environment. Cyanobacteria are photosynthetic organisms that produced oxygen as a by - product of photosynthesis, leading to the oxygenation of the atmosphere.

Answer:

Question 12: C. deep in the oceans near volcanic vents
Question 13: B. oxygenation of the atmosphere