Question

____ on the geologic time scale are marked by major, striking, and worldwide changes in the type of fossils present.

Answer 1

The right answer is a. Eras

A geological era corresponds to the second largest unit of time on the geological time scale behind the eon.

* The history of the Earth is divided into ten eras:

Eoarchéen: -4.0 to -3.6 billion years;

Paleoarchean: from -3.6 to -3.2 billion years;

Mesoarchean: from -3.2 to -2.8 billion years;

Neoarcheen: -2.8 to -2.5 billion years;

Paleoproterozoic: -2.5 to -1.6 billion years;

Mesoproterozoic: -1.6 to -1 billion years;

Neoproterozoic: from -1 to -0.541 billion years;

Paleozoic: from -541 to -252 million years ago;

Mesozoic: from -252 to -66 million years;

Cenozoic: from -66 million years to the present day.

Answer 2

Answer:

The right answer is a. Eras

Explanation:

A geological era corresponds to the second largest unit of time on the geological time scale behind the eon.

* The history of the Earth is divided into ten eras:

Eoarchéen: -4.0 to -3.6 billion years;

Paleoarchean: from -3.6 to -3.2 billion years;

Mesoarchean: from -3.2 to -2.8 billion years;

Neoarcheen: -2.8 to -2.5 billion years;

Paleoproterozoic: -2.5 to -1.6 billion years;

Mesoproterozoic: -1.6 to -1 billion years;

Neoproterozoic: from -1 to -0.541 billion years;

Paleozoic: from -541 to -252 million years ago;

Mesozoic: from -252 to -66 million years;

Cenozoic: from -66 million years to the present day.