well layer A. is the most recent meaning it was there for maybe 100 years
over time you uncover more layers layer B . for example is lowerr then layer A. which is probably 300 years older then layer A.
then you go further down and ou find layerC. which is probably 500 to 900 years older then layer B . then at the very bottom you have layer D. which is about 1300 to about 1700 feet deeper then layer C.
plz mark brainliest
The deeper you go down in to the rock the older the fossils get. So when the scientists go in to the rock they can say what animals lived in that time and what animal was the oldest.
