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.
Answer:
A- A demonstration shows how something works, often including models
Explanation:
A demonstration allows, through experimentation, to show how nature works and in that way can include the explanation of scientific theories that explain the set of observed facts, that is, it serves as a demonstration of the underlying scientific principles.
It's velocity is not constant as direction is changing.
We know, velocity is speed with direction, so if direction is changing, velocity can't be constant, doesn't matter that speed is constant.
Hope this helps!
Answer:
130 km at 35.38 degrees north of east
Explanation:
Suppose the HQ is at the origin (x = 0, y = 0)
So the coordinates of the helicopter after the 1st flight is


After the 2nd flight its coordinate would be:


So in order to fly back to its HQ it must fly a distance and direction of
north of east