1.) According to Newton's first law of motion, the state of motion of an object does not change as long as the net force acting on it is zero.
2.) According to Newton's second law of motion, the acceleration of an object is equal to the net force acting on it divided by the object's mass.
3.) Mass is a measure of the inertia of an object; weight is a measure of the force of gravity acting on an object.
4.) It's easier to move a phone than a large rock, and you can carry the phone at a faster speed then you could with a rock. It's easier to walk without anything than to walk carrying a backpack.
5.) The wooden ball because it has less mass, so air resistance and the force of gravity will equal out faster.