Nobody knows the age of Earth exactly.

Seriously I have no clue....but I do know that my nephew is on a team doing research studing different forms of life and how they came into existance....but as far as your question is concerned.....I don't have a clue.

The Earth is accepted by scientists to be around 4.5 billion years old. http://www.talkorigins.org/faqs/faq-age-of-earth.html But the exact age??? Like you said, nobody knows.

I do not know if scientist were able to determine the actual age of earth. I think they are just making an approximation of the date. But perhaps later on they will be able to determine the actual age to continues study.

No one exactly knowing about age of earth even scientist or expert people. We live in others place before world created by many years ago. If we go to ask anyone here, I am sure it can be wrong answer. Because the world has been re-create for some reason why and when. From prehistoric and historic age, we don't exactly know the true history because we don't look at that age. I guess it can be over billions of years ago.

Hello friend, I remember it from a book in my junior school days. The age of Earth as well as the entire solar system's formation is believed to be some 4.5 billion years ago. I read about it in the big bang theory in all that. I hope its true. It's amazing how much science has progressed. They use radio carbon dating methods to find out these facts.