Amovie theater conducted a survey to see what customers preferred at the concession stand. the theater asked every fifth person who entered the movie theater every friday for a month what his or her favorite movie snack was. were the results of the survey valid? yes, because the theater surveyed a random sample. yes, because the theater only surveyed children. no, because the theater did not survey everyone in the theater. no, because the theater did not use a random sample.