I'm not sure if I got this right or not:

Let A = {n is in Z such that n = 5r for some integer r}

and

Let B = {m is in Z such that m = 20s for some integer s}

* Z is the set of all integers

1) Is A a subset of B?

2) Is B a subset of A?

My reasoning:

1) No (because every time r is odd there is a new value of n in A which does not appear in B)

2) Yes (because no matter what s is there is a m value in B which matches a n value in A)

Is my reasoning sound for these? Thanks for the help!