Write details that describe new york's bodies of water

An education expert is researching teaching methods and wishes to interview teachers from a particular school district. she randomly selects ten schools from the district and interviews all of the teachers at the selected schools. which type of sample did she use in this study? a)systematic sample b)probability sample c)stratified sample d)cluster sample

Experiment to investigate effect of medication on levels of stress in males and females. dependant variable?

To your knowledge had the usa ever invaded canada after the war of 1812