Answer:
As of July 2017, the International Union for Conservation of Nature (IUCN) lists <em><u>455</u></em> critically endangered fish species. Hope this helps!
The tectonic plates<span> are made up of </span>Earth's<span> crust and the upper part of the mantle</span>layer<span> underneath. Together the crust and upper mantle are called the lithosphere and they extend about 80 km deep.</span>
Cracks in a rock is considered is chemical weathering.
The oldest fossils present at the bottom of rock layer whereas the youngest fossils are present in the top layer.
<h2>Rock layers from oldest to youngest</h2>
The rock layers that is located farthest from the ground surface are considered as the oldest rock layers and rock layers that are closest to the ground surface are considered as the youngest. A fossil is the remains or traces of plants and animals that lived long ago.
<h3>Presence of fossil</h3>
Those fossils which are present at the bottom of the rock layers are considered as the oldest fossil followed by the upper layer's fossil and so on. The fossils present at the top layer are the youngest fossils so we can conclude that oldest fossils present at the bottom of rock layer whereas the youngest fossils are present in the top layer.
Learn more about rock layer here: brainly.com/question/14545004
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Drinking water i hope this helps