I don't really know but I pick b.have always been vestigial.
Scientists figured out that the outer core must be liquid because S waves do not pass through it, but P waves do. The behavior of P and S waves also indicates that the inner core is solid. The speed of seismic waves also depends on the density of the material through which they are traveling.
We do a little more about how much you want to be the first to know that the government is not cycled rest he's sleep woe
Answer:
The history of Earth covers approximately 4 billion years (4,567,000,000 years), from Earth's formation out of the solar nebula to the present. Earth formed as part of the birth of the solar system: what eventually became the solar system initially existed as a large, rotating cloud of dust and gas.
Explanation:
