Why on earth would you want to deliberately produce more crossbreeds in a world overrun with them and where they are being put down by the hundreds every week, and from two breeds that are known to have health problems, and from one breed that can have severe behavioural problems? There are more staffs and staff crosses in Battersea than mongrels.
By the way, if you don't know the answer to your question, you should definitely not be breeding dogs of any sort.
Now feel free to sling the insults.