Special Pattern on Cube

Q.

Find the value of x and y respectively.
$8^3$ - $7^3$ = 1 + x $\times$ y $\times$​ 3

1. 8, 7

2. 8, 6

3. 6, 8
4. 7, 9

Q. Choose the correct pair.

1. Perfect cube
2. Perfect square
3. Palindrome
4. 125
5. 16
6. 12321