Answers

2016-07-11T21:31:01+08:00
Rainfall

Scientists think oceans may have formed after millions of years of

Planetesimals

What bodies in the solar system collided and combined to form Earth?

Carbon dioxide and water vapor.

Scientists think that earth's first atmosphere was made up of

Gravity and heat.

What factors caused the shape and structure of the earth?

Photosynthesis

Early life-forms released oxygen into the earth's atmosphere through the process of

Crust

The layer of earth that has the lightest elements is the

Mantle

The middle layer of earth is the

Heavier and lighter elements separated.

Earth's layers formed as rocks melted and

Core

The layer of earth that extends to the planet's center is the

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