Can anyone help with identifying the layers of the earth? Im having a hard time paying attention.

What are the answers for the following questions?

What statement about charlemagne is not true? a. charlemagne's empire collapsed during his rule b. charlemagne sent missionaries throughout europe c. charlemagne encouraged the arts and education d. charlemagne ruled much of western europe a. charlemagne's empire collapsed during his rule

What is the border between layers a through f and layer g called?