The force of earth's gravitational field is always directed downwards (towards the center of the earth. When the ball is thrown up, it is going against the earth's gravitational field and so, the earth's gravitational force pulls it back down, accelerating it downwards.
Answer:
the potential energy a massive object has in relation to another massive object due to gravity
here's the first part but for the 2nd one all I know is that the word "compression" goes on the spirals that are closer together.
hope this helps!