so on 2^7i list i as -1 seven times equals out -1 or -i then what

i still cant solve i^100

powers of i cycle through.

i^0 = 1
i^1 = i
i^2 = -1
i^3 = -1
i^4 = 1
and so on.

i^100 = (i^4)^25 = 1^25 = 1

I can't figure out what you're asking on the first part.