Answer:
Molecule
Explanation:
A molecule is a term that refers to the smallest unit of a molecular compound with the properties of the compounds.
Molecules are like what atoms are to elements.
Every molecule of a compound possess the unique characteristics of the compound thereby typifying it.
The term molecule is often used to denote a covalent compound with a discrete or separate unit.
Because this happens in the pacific rim, where the most volcanoes and volcanic islands are found
Rift Valley
A rift valley is a lowland region that forms where Earth's tectonic plates move apart, or rift. ...
Tectonic plates are huge, rocky slabs of Earth's lithosphere—its crust and upper mantle. ...
Many rift valleys are part of “triple junctions,” a type of divergent boundary where three tectonic plates meet at about 120° angles.
The fossil remains built up over 185 million years. it was formed through the Jurassic, Triassic and cretaceous periods