Answer:
Cast fossils occur when mold fossils are filled in with minerals that harden over time, creating a fossilized replica of the original organism. Water seeps through the rock surrounding the mold fossil, leaving behind minerals which fill the mold. Any mold fossil can potentially form a cast mold.
Explanation:
Think a plant dones not have a cell wall.
1) The troposphere<span> is the first layer above the surface and contains half of the Earth's atmosphere. </span>Weather<span> occurs in this layer. </span>
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2) Many jet aircrafts fly in the </span>stratosphere<span> because it is very stable. Also, the ozone layer absorbs harmful rays from the Sun.</span>
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3) Meteors or rock fragments burn up in the </span>mesosphere.
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4) The </span>thermosphere<span> is a layer with auroras. It is also where the space shuttle orbits. </span>
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5) The atmosphere merges into space in the extremely thin </span>exosphere<span>. This is the upper limit of our atmosphere.</span>
Because they have been living longer