Friction and air resistance are forces that always: 1.) Balance out, having no effect on the net force.

2.) Act in the opposite direction to an object's motion, tending to slow it down.

3.) Pull objects down towards the center of the Earth.

4.) Cause objects to speed up.

Explanation:

https://www.khanacademy.org/science/physics/forces-newtons-laws/balanced-unbalanced-forces/v/unbalanced-forces-and-motion

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.

i think it would be 5