If I am taking advanced placement (AP) classes in high school, is it mandatory to take the college board ap exam?

Ahigh school teacher wants to study the seating habits of students in the cafeteria to determine if students sit in the same seats or change seats from day to day. she sits in the cafeteria for several days, and without interacting with the students, records where they sit each day. what is a potential benefit of this type of research? there is an independent variable. there is a dependent variable. the researcher can gain personal information about an individual. the participants act normally. the information can be gathered over a period of several years.