The Earth is over 4.5 billion years old and was formed with leftover material not long after the formation of the Sun.
How long ago were primitive life forms living on our world?
900 million years / 2.1 billion years / 3.7 billion years
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Answer to question 6 / 3.7 billion years.
Consider yourself very special and unique, the odds against you being here are astronomical and extremely close to zero.
Part of that odds is that you are the latest result of an unbroken chain of reproduction that started well over 3 billion years ago.