Maths Factorize problem 20p

1. 2(a+b)(p-q)+4(q-p)(x+y)
2. 18(p-q)^3-12(q-p)^2
3. 5y(y+3)^2+(3+y)^2-
4. (x-y)^2(m-n)^3+(y-x)^3(n-m)^4
From 5-9 some is impossible to factorize
5 au+av-bv+bu
6.5x-5y-2ax-2ay
7.4(rs^2-r^2)+st(1-16r)
8. 3b-3bc-c-4ac+12ab+6b^2
9.18m+3n+24m^2-8mp+4mn-6p