Can some one tell me the answer I need to find the domain and range for this question​

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

1. if we have 3 babies what is the probability they’re going to be all boys? 2. if we roll 2 die at the same time what is the probability of getting less than 10 on the first roll and a 5 on the second roll 3. if we have 3 babies what is the probability their is going to be 2 girls? 4. if we have 3 babies what is the probability of having no more than 1 girl? 5. it we have 3 babies and then have another 3 babies what is the probability of us having at least 1 boy and then having all girls?

Ineed someone to me answer my question i have to have this done and knocked out