A small cube with side length 6y is placed inside a larger cube with side length 4x^2. What is the difference in the volume of the cubes? - 1) (4x^2 - 6y) (16x^4 + 24x^2y + 36y^2)
2) (6y - 4x^2) (36y^2 + 24x^2y + 16x^4)
3) (4x^2 - 6y)(4x^4 + 24x^2y + 6y^2)
4) (4x^2 + 6y) (16x^4 - 24x^2y+ 36y^2) ​