Suppose that we plan to evaluate a classroom based prevention aiming to reduce school dropout rates. We will use a randomized controlled trial to assign the students to control or treatment conditions. To determine how many participants should be recruited for the study, you have collected the following information, level of significance = .05, minimum power required = .80, and the dropout rate of the control schools is 20%. What additional information will you need to calculate the sample size? Group of answer choices The social ecomic status of the potential participants. The funding limit of the study. Size of expected treatment effect. The geographic scope of the proposed study