Smith and cuvier discovered that similar groups of fossils in distant rock layers could be correlated. why was this such a major breakthrough in geology?

a. it disproved the principle of superposition.
b. it proved igneous rocks held more information than sedimentary rocks.
c. fossils could now be used to identify rock layers.
d. fossils were no longer needed to study the history of earth.

An unknown substance is a white solid at room temperature and has a melting point of 78 °c. which of the following substances is most likely to be the identity of the unknown sample? a. naphthalene, a molecular solid with the formula c10h8 b. silica, a network solid held together by covalent bonds with the formula sio2 c. calcium chloride, an ionic compound with the formula cacl2 d. water, an molecular compound with the formula h2o