Which invention led to an increase in the production of cotton and southern farms become more productive?

Why do all market economies have taxes to support armed forces police forces public schools and at least some form of public transportation?

How did nationalism transform the identity of africans

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