Question

If T = {positive integers} and subset W = {5, 10, 15, 20, …}, what is W'?

{1, 2, 3, …}

{positive integers except those divisible by 5}

{5, 10, 15, 20, …}

{ }

Answer 1

I think it's A

Answer 2

{5, 10, 15, 20, …}