Final answer:
Volcanoes are formed when magma reaches the surface and cools, creating new landmass.
Step-by-step explanation:
When magma reaches the surface and cools, creating new landmass, it forms a volcano. Volcanoes are geological features that result from the eruption of magma, or molten rock, onto the Earth's surface. As the magma cools and solidifies, it builds up layers of volcanic material, forming a distinct landform.
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