Unless the subject matter is considered common knowledge, citations are necessary when writing about:

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

Most galaxies in the universe are irregular-shaped galaxies. true or false ?

What kind of new warfare did the patriots use in the south? what does it mean?