Why are there no rocks from when earth was first formed?
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What is an example of a line segment

The blue segment below is a diameter of oo. what is the length of the radius of the circle?

When volcanoes erupt, magma (hot, molten rock) rises toward the surface of the earth. as magma cools, solid rock forms. this rock contains substances from the interior of the earth. which of the following natural resources is likely to be plentiful near subduction zones where volcanic activity has occurred in the past?