There 100 students and 100 lockers the 1 student go amd open all the lockers and the 2 studen go to the second locker and start ckosing every 2 lockers like 2 then 4 then 6 so on then the 4 studne go to the 4 locker and opened but if the lockrr is open he closed but if is close he opened and same thing with the rest of the student hiw many locker would be ckose and open after the 100 studen pass