input: Write a function to find the k-th smallest element in a list using sorting.
  assert find_kth_smallest([7, 10, 4, 3, 20, 15], 3) == 7
  assert find_kth_smallest([7, 10, 4, 3, 20, 15], 4) == 10
  assert find_kth_smallest([12, 3, 5, 7, 19], 2) == 5
  assert find_kth_smallest([1, 2, 3, 4, 5], 5) == 5
output: def find_kth_smallest(arr, k):
      arr.sort()
      return arr[k - 1]