What do we know about the internal structures in the Earth’s inner core-how can seismological methods reveal them?

Short answer questions- Plate Tectonics & Global Geophysics

There are 2 questions to be answered (max 200 words per question), preferably one with 5 and another one with 6 cited sources, recently published/ relevant research papers. One or two diagrams included per question (example answers included in assignment instructions).

This has to be a concise answer to the issue, ‘academic dictionary – like’.

Questions to be answered:

1.What is our current best understanding of the accretion of the Earth?

3.What do we know about the internal structures in the Earth’s inner core, and how can seismological methods reveal them?