Factoring?! HELP! i have no clue how to do this?!?

Question

i have no clue how to do these math problems, and i reallly am frustarated with all my math homework oy, soemone want to give me the answers and explain how to do them?

by the way the ^ means powers like 2 to the foruth would look like this

2^4.

NOW THESE ARE THE PROBLEMS.

m^6 - 81

9m^2n^2 -12mn+4

16p^2 - 40p +25

those are some examples! helppppppp.

Answer 1

m^6 - 81 = (m^3 - 9) (m^3 + 9)

9m^2n^2 -12mn+4 = (3mn - 2) (3mn - 2) or (3mn-2)^2

16p^2 - 40p +25 = (4p - 5) (4p - 5) or (4p - 5)^2