Benjamin entered a pizza-eating contest when he was in college. he finished five large pizzas by himself, but he felt nauseated and threw up a few hours later. for several years, the sight and smell of pizza made him feel sick. in this scenario, benjamin's aversion toward pizza occurred through

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