pencils falling from the same height balloons floating upward from the same height a bicycle speeding up on a flat surface a ball slowing down on a flat surface
Which investigation will best test the effects of gravity on moving objects?

Options:
- pencils falling from the same height
- balloons floating upward from the same height
- a bicycle speeding up on a flat surface
- a ball slowing down on a flat surface

pencils falling from the same height