The two items used to determine absolute age are:
3. Carbon dating & index fossils
Carbon dating is a method used to determine the absolute age of ancient organic materials, while index fossils are used in relative dating to establish the age of rock layers and can help correlate the age of fossils with other stratigraphic data. However, it's important to note that while index fossils are more commonly associated with relative dating, they can also be used in conjunction with absolute dating techniques to better understand geological time.