A group of students conduct a survey at their high school to see how many students would like a snack to be offered at the bus ramp before school. Of those students, students ride the bus to and from school, drive a car to school, students walk to school, and students are dropped off and picked up by a family member. The school has 6500 students which uses the given mode of transport eqully. What is the size of the population of this survey?