Question

1) The product of cube roots of -1 is equal to?
2) The product of n nth roots is?
3) If ω is the cube root of unity then (1-ω+ω^2)^6 + (1-ω^2+ω)^6 is?

Answer 1

i only know the answer of the first 
it will be -1 since -1*-1*-1=-1