A sample of 30 dentists from Seattle is taken to estimate the median income of all Seattle residents Is this study A REPRESENTATIVE O B NON REPRESENTATIVE A simple random sample of men over age 18 is taken to estimate the mean weight of all adult males Is this study A REPRESENTATIVE B NON REPRESENTATIVE A telephone survey is conducted during the day in order to determine the chances of a certain candidate winning an election Is this study OA REPRESENTATIVE B NON REPRESENTATIVE A simple random sample of 40 U S citizens is taken in order to estimate the mean cholesterol level of U S citizens Is this study O A REPRESENTATIVE B NON REPRESENTATIVE