II. Choose the letter of the correct answer. 11. Magnets have force that attracts materials made of a. copper b. wood c. plastic d. iron 12. When two magnets attract, they a. pull together b. change color c. break d. push apart 13. When two magnets repel, they a. break b. pull together c. push apart d. change color 14. Magnets have two ends, the north and south a. region b. color c. pole d. corner 15. When magnets are the force of magnetism is stronger. a. farther apart b. rectangular c. round d. closer together 16. If you break a magnet into pieces, the force exerted by it will a. stay the same b. decrease c. increase d. get stronger 17. Magnets have invisible a. magnetic field b. electric current C. sound waves d. signals 18. The place where magnetic force of a magnet is strongest is at a. ends b. edge c. sides d. all parts