16) n³ - 27p⁶ =

Rewrite 27p⁶ as (3p²)³:

n³ - (3p²)³

Apply the difference of cubes formula:

(n - 3p²)(n² + n(3p²) + (3p²)²)

(n - 3p²)(n² + 3np² + 9p⁴)