Answer:
The simplest mechanism by which molecules can cross the plasma membrane is passive diffusion. Passive diffusion is thus a nonselective process by which any molecule able to dissolve in the phospholipid bilayer is able to cross the plasma membrane and equilibrate between the inside and outside of the cell.
Please fix your question, and this belongs in science, not biology. When the ball hits it's maximum height, it's kinetic energy will change to zero, and it will be converted to potential energy.
