There are n concentric squares. The area of the innermost square is 1 unit and the distance between corresponding corners of any two consecutive squares is 1 unit. Consider the following statements:
I. The diagonal of the n^th square is 2n + √2 - 2
II. The area included between the n^th square and the (n - 1)^th square is independent of n
Which of the statements given above is/are correct?