Question

Please help me, I really need someone

Answer 1

The (horizontal) green line describes an object that's not moving.

Whatever TIME you pick to look at the green line, its POSITION is always the same. This is a pretty good description of "not moving".

The other three lines all have different positions at different times, so they all describe motion.

Answer 2

In plotting position versus time it can be seen that the green line represents a fixed position at the various times given - the other lines represent changing position with time