1. Twenty percent of the library books in the fiction section are worn and need replacement. Ten percent of the nonfiction holdings are worn and need replacement. The library's holdings are 40% fiction and 60% nonfiction. Use a tree diagram to find the probability that a book chosen at random from this library is worn and needs replacement?
2. In a recent environmental study of 440 copper and galvanized steel water lines in Flint, Michigan, 77% of the lines were copper and 23% were galvanized steel. The study demonstrated that water in 6% of the copper lines had elevated levels of lead (above 15 parts per billion), while water in 11% of the galvanized lines had elevated lead levels. Use a tree diagram to find the probability that a water line chosen at random has elevated water lead levels?