Which of the following statements accurately describes the process of dating earth's history?

a. scientists use radioactive isotopes to determine the absolute age of a new fossil.
b. scientists use relative dating to determine the absolute age of a new fossil.
c. scientists use radiometric dating to determine the relative age of a new fossil.
d. scientists use index fossils to determine the specific years of age of a new fossil.

Cladistics is a way of classifying organisms by examining the characteristics of their ancestors and descendants and depicting the relationships in a cladogram. which of the following best describes a challenge in classifying organisms this way? a. there are millions of species on earth, and a cladogram is not a practical means for classifying all of them. b. it is impossible to tell which organisms are most closely related to each other using a cladogram. c. cladograms are detail-oriented and do not provide a useful understanding of evolutionary relationships. d. there is a limited number of ways to organize the information, so most cladograms end up looking very similar.