Which expression is equivalent to (6x⁵z)³ over 4x⁴z²?
1) (6x⁵z)⁹ over 4x⁴z²
2) (6x¹⁵z³) over 4x⁴z²
3) (6x⁸z³) over 4x⁴z²
4) (6x⁵z)³ over 16x⁴z²