2. does the bowling ball have more potential energy or kinetic energy as it is half way through its fall
.

Equal

Explanation:

Recall that KE = 1/2(m)(v²) and PE = mgh, where m is mass, g is gravity, v is velocity, and h is height.

When the bowling ball is first dropped, it has a maximum potential energy but minimum kinetic energy.  The height is max, so the potential energy will be greatest.  Velocity is 0, so kinetic energy will be 0.

When the bowling ball is half way through its fall, the height will be half the initial height and the velocity will be half of the final velocity.

When the bowling ball is at the bottom and reaches the ground, the height is 0 so potential energy is 0 while the kinetic energy is max because velocity is the greatest.

when it gains or loses electrons

3. dark matter

empty space could also be a simple vacuum