The video explains the nebula theory, suggesting our solar system formed from a nebula disrupted by a supernova. This led to the creation of the sun and planets, including Earth, which formed 4.6 billion years ago. The Precambrian Era, lasting nearly 4 billion years, accounts for over 85% of Earth's history. Rocks from this era can still be found in North America. Life began in the oceans with microscopic bacteria, followed by early plants and simple ocean animals like jellyfish and corals.

What event is believed to have triggered the formation of our solar system according to the nebula theory?

• A collision with another galaxy

• A massive asteroid impact

• A nearby star's supernova explosion

• The Big Bang

How long did the Precambrian era last?

• Approximately 500 million years

• Nearly 4 billion years

• About 1 billion years

• Around 2 billion years

Where can rocks from the Precambrian era be found in North America?

• In the Sierra Nevada

• In the Rocky Mountains

• In the Great Lakes region

• In the Appalachian Mountains

What form of life first appeared in the early oceans during the Precambrian era?

• Birds

• Dinosaurs

• Microscopic bacteria

• Mammals

Which of the following simple ocean animals appeared toward the end of the Precambrian era?

• Fish

• Jellyfish

• Reptiles

• Amphibians