Which if these descriptions best matches feudalism

Which of the following is a reason why people are vacationing in slovakia

Brian's school locker has a three-digit combination lock that can be set using the numbers 5 to 9 (including 5 and 9), without repeating a number. the probability that the locker code begins with a prime number is %. the probability that the last digit of the locker code is an odd number is %.

What is the border between layers a through f and layer g called?