12. When two magnets attract, they, A. Break apart B. Change color, C. Pull together, D. Push together, 13. When two magnets repel, they, A. Break apart B. Change color, C. Pull together, D. Push together, 14. Magnets have two ends, the north and south, A. color, C. pole, B. corner, D. region, 15. Magnets have invisible, A. Electric current, B. Magnetic field, C. signals, D. sound waves