Everyone i need help so much

Which force is most responsible for binding together an atom's protons and neutrons? electrostatic gravitational nuclear magnetic

Which units can be used to measure length or distance? check all that apply. gram meter kilometer liter inch

Part 1: a magnetic levitation or maglev train rides rails without touching them. explain how this works using your data. include the appropriate magnet drawing in your answer. part 2: two objects are near a bar magnet. one is about 1 cm away, while the other is 6 cm away. compare and contrast the magnetic force that affects each object. use your data to answer the question