The principal at marina middle school wants to determine if the 120 students in the seventh grade prefer to visit catalina island or camp mosaic for their end-of-year trip. which of the following is a representative sample of the population? select all that apply. a. 20 sixth-grade students, 20 seventh-grade students, and 20 eighth-grade students b. 10 seventh-grade boys and 10 seventh-grade girls c. 25 seventh-grade students d. 15 seventh-grade boys and 5 teachers e. 25 students from the school