What fossils lived in the Silurian time period? (THERE IS ALSO A FOURTH CHOICE):

4th choice: Eurypterus, Condor, Eucalyptocrinus

7. according to the theory of isostasy, which statement must be true? a. the asthenosphere is denser than the lithosphere. b. the asthenosphere has the same density as the lithosphere. c. the lithosphere has the same density as the core. d. the lithosphere is denser than the asthenosphere.

People make choices about how to use resources.

Scientists believe that differences in cause hot, plastic-like rock in the asthenosphere to rise toward earth's surface. a. density c. weight b. magnetism d. composition c. conduction. d. density.