How many active volcanoes are there in the united states

Magma forms by partial melting of upper mantle and crust. partial melt means that only a fraction of the available material forms a melt, and that the remainder stays solid. the partial melt rises because of its lower density and ascends through he crust. this is so conclusive mean the answer would be magma igneous rocks or balistic magma.

The answer is itprovides information about locationis a network of satellites orbiting the earth

Either b or c . i did this before