On the long list of happy ＿＿（5）＿＿ in science, some discoveries prove to be more monumental than others. Stephanie Kwolek's was just such a landmark. In the mid-1960s, Kwolek was working at Dupont, ＿＿（6）＿＿ a new synthetic fiber to use in tires. She noticed that one mixture of a polymer and a solvent looked different. ＿＿（7）＿＿ assuming she'd made a mistake, she was ＿＿（8）＿＿ and followed up on her observation. When her formula was spun into fiber, it proved to be five times as strong as steel. With its unusual protective powers, it is used in bulletproof vests, body armor and workers' gloves, which helped to save lives and avoid cuts. It has also been used to ＿＿（9）＿＿ items from boats and cookware to wind turbines and cell phones.