Supposing the half-life of element X to be 1 year, if you have a 100 gram sample of X, how much of element X would be left after 4 years? (Do not use significant digits in answering this question.) 75 g
50 g
25 g
6.25 g

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