Which changes occur in the composition of the earths layers from the surface to the core

Why are fossils of organism's from the phanerozoic eon much more likely to be found than fossils of organisms from any other eon? a. more organisms present during the phanerozoic eon had soft body parts. b. organisms present during the phanerozoic eon were all microscopic. c. more organisms present during the phanerozoic eon had hard body parts. d. organisms present during the phanerozoic eon are the most ancient life forms.

Which of the following is not a place where hydrogen can be found on earth? a. natural gas well b. atmosphere c. water d. mine

Name one type of data that h-r diagrams do not show.