Earth's History

Trilobites are found in the _____________.

• Cenozoic
• Mesozoic
• Paleozoic
• Cretaceous

The Precambrian is the ___________ time span in Earth's history.

• youngest
• latest
• earliest
• middle

Current scientific evidence shows that the Earth is estimated to be: 

• Less than 1 millions years old
• Between 3 and 4 billion years old
• More than 4 billions years old
• Less than 2 billion years old

The second largest category of geologic time is______________?. The Cenozoic is one of them.

• era

• eon

• epoch

• period

The Phanerozoic is a

• eon

• era

• period

• epoch

The Cenozoic is a

• eon

• era

• period

• epoch

What are the names of ALL parts of the geologic time scale in correct order from broadest to narrowest?

• era, period, eon

• eon, era, period, epoch

• era, eon, epoch, period

• eon, era, epoch, period

The period of time where conditions were harsh and no life forms existed was the

• Pleistocene

• Cambrian

• Hadean

• Holocene

Known as the age of reptiles

• Mesozoic

• Cenozoic

• Phanerozoic

• Cambrian

Mammals are a dominant group in which era?

• Cenozoic

• Mesozoic

• Paleozoic

• Cambrianozoic