Work out the gradient of the slope if Point A has a height of 640 meters, Point B has a height of 590 meters, the distance between the two points is 15km

Answerscripps institution of oceanography; i believe this is correct plz check first good luck;

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.