As the earth has active tectonics we know that rocks are recycled and the oldest rocks may therefore just be the oldest rocks that have not been recycled yet. We know the true age of the earth by looking at radioactive isotopes of things like spacedust and meteors that formed at the same time as the earth as they have not been affected by the tectonic process of recycling here on Earth.
B i think!! hope this helped
more similar to bacterial cells
These are the most common symptoms associated with PSTD
