An example of a closed system is
, while an example of an open system is.

The graph describes the motion of an object. the object moves with from a to b. it from b to c. it moves with from c to d.

According to newton’s law of universal gravitation, which statements are true? as we move to higher altitudes, the force of gravity on us decreases. as we move to higher altitudes, the force of gravity on us increases. as we gain mass, the force of gravity on us decreases. as we gain mass, the force of gravity on us increases. as we move faster, the force of gravity on us increases.

While carrying a heavy box up the stairs, you set the box on a step and rest. then you pick up the box and carry it to the top of the stairs. describe these actions in terms of balanced and unbalanced forces acting on the box.