Pls help me.......with solution pls..thanks GOD Bless

Question

1.)3mn^3(10m^8n^9-6m^3n^8-11m^4n^12)

2.)(2x 4y-76)^2

3.)(2x 3y)(3x-4y)

4.)(11-y)(11-y)

5.)[(x-y) 3]^2

Answer 1

1.)30m^9n^12 - 18m^4n^11 - 33m^5n^15

2.)4x^2 + 16xy - 304x + 16y^2 - 608y - 5776

3.)6x^2 + xy - 12y^2

4.)121 - 22y + y^2

5.)(x-y)^2 + 6(x-y) + 9