A school principal wants to know what theme students prefer for the spring dance. There are 150 students in the 6th grade, 200 students in the 7th grade, and 187 students in the 8th grade. Select all the representative samples that can help the principal draw conclusions about which themes the students prefer.
The students in the 7th grade homerooms,
The same number of students from each grade whose names are randomly selected from a hat
The members of the student council
Students who attended the winter dance
50 sixth graders, 67 seventh graders, and 62 eighth graders