Simplify:
i. (m2 - n2/(m + n)2) x (m2 + mn + n2/(m3 - n3))
ii. (a2 + 10a + 21/(a2 + 6a - 7)) x (a2 - 1/(a + 3))
iii. (8x3 - 27y3/(4x2 - 9y2))
iv. (x2 - 5x - 24/(x + 3)(x + 8)) x (x2 - 64/(x - 8)2)
v. (3x2 - x - 2/(x2 - 7x + 12)) / (3x2 - 7x - 6/(x2 - 4))
vi. (4x2 - 11x + 6/(16x2 - 9)
vii. (a3 - 27/(5a2 - 16a + 3) / (a2 + 3a + 9/(25a2 - 1))
viii. (1 - 2x + x2/(1 - x3)) x (1 + x + x2/(1 + x))