Sagot :
Answer:
An object is in motion if its distance relative to another object is changing. To tell if an object is moving, you use a reference point. If an object's distance from another object [reference point] is changing.
hope it helps
Answer:
An object is in motion if it is moving away from or towards another object. To tell if an object is moving, use a reference point. If the distance between two objects is changing, then one or both of the objects may be moving.