I would choose count of electron shells and count of valence electrons. The electron configuration of each element is fixed and can be used to determine the element's identity. By counting the electron shells, you can have an idea which part of the periodic table the mystery element lies, and by determining the number of valence electrons (outermost shell), you can pinpoint the exact identity of the mystery element.
Crustal deformation builds landforms when two tectonic plates start to push into each other they can rise up and build mountains, or when they sink under, they create valleys.
<h3>How crustal deformation builds landforms?</h3>
Tectonic pressure in a crust can cause folding. Folding can end up with the formation of valleys and mountains so we can conclude that when two tectonic plates start to push into each other they can rise up and build mountains, or when they sink under, they create deep valleys.
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