Rock is millions of years old- this statement is correct about heroes finding.
Step-by-step explanation:
In rock formation, igneous rock formed first due to volcanic eruption. When lava cooled down and solidified it formed igneous rock after that when this rock undergone some physical changes due to weathering and denudation it formed sedimentary rock.
Sedimentary rock contains footprints of animals and impression of body parts of animals and plants called fossils. It takes millions of years to form. Sedimentary rock is known as layered or stratified rock as it contains several layers of sediments which get deposited over millions of years.