Question 326786
"Closed under multiplication means that any member of the set times any other member of the set (including itself) yields another member of the set.

Note: 0×0 = 0, 0×1 = 0, 1×1 = 1

Those are all possible combinations and all yield a member of the set.

So, yes the set is closed to multiplication."
this was taken of yahoo answers for this same question 11months ago
by ProfRay.