Final answer:
A volcano is a vent or hole in Earth's surface through which melted rock or ash erupt. It can form cone-shaped structures on land where pyroclastic material is ejected.
Step-by-step explanation:
A volcano is a vent or hole in Earth's surface through which melted rock or ash erupt. When pressure builds up beneath the Earth's surface, molten rock, called magma, rises to the surface and is ejected through the volcano's vent in the form of lava, gases, and volcanic ash. This volcanic activity can lead to the formation of cone-shaped structures on land where pyroclastic material is ejected.
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