When did life first appear on the planet?3.5 million years ago3.5 billion years ago2.1 million years ago2.1 billion years ago

It was in the primitive oceans that life began almost ___________ billion years back.A 1 B 3.5 C 2.5 D 6

The first animals arose on Earth approximately ______ years ago.Multiple choice question.570 million900 million140 million750 million

Homo sapiens first appeared approximatelyChoose 1 answer:Choose 1 answer:(Choice A)   50,000 years agoA50,000 years ago(Choice B)   200,000 years agoB200,000 years ago(Choice C)   800,000 years agoC800,000 years ago

The earliest possible time that life could have started is generally believed to be:Group of answer choicesThe beginning of the Archaean eonThe beginning of the Proterozoic eonThe beginning of the Hadean eonThe beginning of the Phanerozoic eon

1 billion years after the big bang the first ______ begin to form. (our notes said 500,000,000 years)*1 pointPlanetsStarsGalaxiesLightAtoms