Dr. stroetz believes that most psychological disorders can be successfully treated by bringing unconscious conflicts and defenses into conscious awareness. knowing this, you might expect that dr. stroetz's bookshelves contain a large number of books written by

Donald is studying the eating habits of all students attending his school. he samples the population by dividing the students into groups by grade level and randomly selecting a proportionate number of students from each group. he then collects data from the sample. which type of sampling is used? select the correct answer below: systematic sampling convenience sampling stratified sampling cluster sampling