8. Which of the following are reasons why Index fossils are chosen for determining ages of rocks? Select all that apply . A Found commonly in rocks
B. Distributed over a very wide range
C. Are always dinosaurs
D. Limited life existence in geologic time.

B. Distributed over a very wide range

D. Limited life existence in geologic time.

Explanation:

Index fossils are very unique fossils that helps in determining the relative ages of rocks and biostratigraphic correlation. They are usually called guide fossils.

Fossils are the preserved remains of dead organisms found in rocks. Index fossils are a special class of fossils with the following properties; They are widely distributed. They have a short stratigraphic range. They show rapid evolution trends

Abbreviated as mg-25.

Particle exchange energy though elastic collision , hope this .