Question

what are fossils?? how do we know how old the fossils are???​

Answer 1

Answer:

A fossil is any preserved remains , impression, or trace of any once living thing from a past geological age .

Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of know ages .

Answer 2

Answer:

A fossil is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood, oil, coal, and DNA remnants. 

There are two methods:

(i) Relative method when we dig into the earth, the fossils we find closer to the surface are more recent than the fossils we find in deeper layers.

(ii) By detecting the ratios of different isotopes of the same element in the fossil material.