question 2\nwhat evidence best supports the presence of atmospheric oxygen 2.7 billion years ago?\ncarbon 14…

question 2\nwhat evidence best supports the presence of atmospheric oxygen 2.7 billion years ago?\ncarbon 14 in plants\nlayered iron rust in rocks\norganic material in meteorites\nfossils found in stomatolites

question 2\nwhat evidence best supports the presence of atmospheric oxygen 2.7 billion years ago?\ncarbon 14 in plants\nlayered iron rust in rocks\norganic material in meteorites\nfossils found in stomatolites

Answer

Brief Explanations:

Iron rust (iron - oxide) forms when iron reacts with oxygen. Layered iron rust in rocks indicates the presence of oxygen in the atmosphere at the time the rocks were formed. Carbon - 14 in plants is related to radioactive dating and not direct evidence of ancient oxygen. Organic material in meteorites is extraterrestrial and not related to Earth's ancient atmosphere. Fossils in stromatolites are related to ancient life forms, not direct evidence of oxygen.

Answer:

layered iron rust in rocks