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olasank [31]
3 years ago
13

How many years ago did the earth cool enough for solid rocks to form ?

Biology
1 answer:
Anestetic [448]3 years ago
3 0
<span>As soon as the crust became </span>cool enough<span> not to remelt, convection driven plate ... as early as 4.2 billion </span>years ago<span>, only 400 million years after the </span>Earth<span> formed.</span>
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<u>Explanation:</u>

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