For what percentage of Earth’s history has life existed on Earth?

Answer 1

Taking Earth's age as nearly 4.6 Billion Years (BY), instead of 13.7 BY from Big Bang, unicellular life appeared nearly 3.8 BY ago. This percentage is 3.8/4.6 X 100 = 82.6%, nearly.

The earliest growing and dividing microbe on Earth appeared approximately 3.8 billion years ago (source: www.bbc-co.uk_nature/history_oftheEarth). This is attributed to the discovery of strong ultraviolet ray absorption, which is correlated with the presence of hydrocarbons.

By signing up, you agree to our Terms of Service and Privacy Policy

Answer 2

Ivy Allen

Almost three-quarters of Earth's history has been inhabited by life.

By signing up, you agree to our Terms of Service and Privacy Policy

Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.