How do scientists know that the world is really 4.5 billion years old?

Question

How do scientists know that the world is really 4.5 billion years old?

Answer 1

Radiometric dating is the primary dating scheme employed by scientists to determine the age of the earth.

Answer 2

By using the half-life measurements of many different elements, some of which have half-lives on the scale of billions of years.

Answer 3

radiocarbon dating

Answer 4

They dont.

They are making ssumptions based on assumed data which changes all the time as they discover more and more about the structure of the universe.

They are slowly finding that the Bible is a handbook of how the earth and its people should work, like a car or washing machine manual.