Our current estimates state that the Earth is about Blank______.Multiple choice question.100 billion years old4.5 billion years old4.5 million years old100 million years old

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

How old is our planet Earth?4.6 billion years old6,000 years old4.6 million years oldWe do not have enough information to accurately date the age of Earth.

Amniotes appeared approximately Blank______ million years ago.Multiple choice question.100200300400

The total number of species that exist worldwide is estimated to be Blank______.Multiple choice question.less than 1 million1.5 millionbetween 8 million and 12 millionbetween 100 million and 115 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