The two major political parties in the united states are a considered part of ?

Which regulatory agency attempts to prevent unfair business practices and consumer fraud?

What are the relation of community dynamics and community action to applied social sciences?

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