Help: operations on sets

let U=Z(integers)
A={x | x is an odd number, x>0}
B={x | x=2^y, y ϵ W}
C={x | x=2^y, y ϵ N}
where W=whole numbers
N=natural numbers

find
a. A ∩ B
b. A' ∩ B
c. (A U C ' ) '
d. (B - C) '

a. A ∩ B = {1}
b. A' ∩ B = C
c. (A U C ' ) ' = A' ∩ C = C
d. (B - C) ' = {x| x ≠ 1}