If z = 2 + 2i, what is z4?
A
2 square root 2 (cosine ( StartFraction pi over 4 EndFraction) plus i sine (StartFraction pi over 4 EndFraction))
B
2 square root 2 (cosine (pi) plus i sine (pi))
C
64 (cosine ( StartFraction pi over 4 EndFraction) plus i sine (StartFraction pi over 4 EndFraction))
D
64 (cosine (pi) plus i sine (pi))