For over 20 years, the Occupational Safety & Health Administration has required companies that handle hazardous chemicals to complete material safety data sheets (MSDSs). These sheets have been criticized for being too hard to understand and complete by workers. Although improvements were implemented in 1990, a recent study of 150 MSDSs revealed that only 11% were completed satisfactorily (Chemical & Engineering News, Feb. 7, 2005). Find an interval that contains the true proportion of all MSDSs that are completed satisfactorily, with 95% confidence. Would it surprise you if the true proportion was as high as 20%? Explain.