1. Glow-inthedark watches are cool. Early in the twentieth century. the luminous hands and numbers on watches were often handpainted by young women in fac tories. In order to keep their brushes sharp for the ne work, they would often lick the brush, thereby ingesting small quantities of radioactive radium. This sim- ple act had tragic consequences. Ingested radium destroyed bone tissue. In some cases, women lost their jaws and. worse, their lives. Draw a graph to illustrate this externality associated with radium-painted watches