According to given question,
If the positions of the first and the sixth digits of the group of digits 3 5 9 7 2 8 0 1 6 4 are interchanged.
New number after interchange = 8 5 9 7 2 3 0 1 6 4
Then the positions of the second and the seventh digits are interchanged.
New number after interchange = 8 0 9 7 2 3 5 1 6 4
After interchanging the number becomes as follows: 8 0 9 7 2 3 5 1 6 4
fourth digit from the right end after the rearrangement : 5