How do fossils help in understanding the history of Earth?

Step-by-step solution

Fossils are described as the remains of the hard parts of life-forms found in rocks.Rocks form sediments and a cross-section of earth's crust indicates the arrangement of sediments one over the other during the long history of earth. Different-aged rock sediments contain fossils of different life-forms who probably died during the formation of the particular sediment. Fossils help in understanding the history of Earth by showing the arrangement of sediments and indicating the geological period in which life-forms e