Russia's eastern to western border is 6,666 miles.
The answer is seafloor spreading. It is a progression that happens at mid-ocean ridges which are the divergent boundaries, where new oceanic crust is made through volcanic activity and then slowly moves away from the ridge. This helps clarify the continental drift theory in the plate tectonics theory.
Discrimination against their ancestor resource: my textbook>
Answer:
Radioactive isotopes are unstable and will decay. ... The isotopes will decay into a stable isotope over time. Scientists can tell how old the rock was from looking at the radioactive isotope's half-life, which tells them how long it would take for there to be half the radioactive isotope and half the stable isotope.