True or false! HELP ME!!! 12. Continental crust extends deeper into the mantle than oceanic crust.
13. Dendrochronology is the limited to the age of the oldest living tree.
14. First fish appeared in the Paleozoic Era.
15. Asteroids are usually smaller than 1km across.
16. By the end of the Proterozoic, all the major masses of continental lithosphere had formed.
17. Global cooling may have caused the Late Ordovician mass extinction.
18. Some fossils of the largest known plants have been found in Carboniferous sediment deposits.
19. The Basin and Range Province formed through compressional tectonism.
20. Iridium is not common in rocks at Earth’s surface.