This is your choice and depends especially to your resistance to cold water.
It's generally not recommended to swim in cold weather as it can increase the risk of hypothermia and other cold-related illnesses. If you do choose to swim in cold weather, make sure you are properly dressed in a wetsuit and take all necessary precautions to stay safe.
they can swim upside down in cold water to
yes it is safe
if you teach them to then i would think they could--also depends on what temperature water u put them in since they have hair (they get really cold really fast in cold water). all dogs should be able to swim--but i would put a dog life vest on just to be safe.
yes it is safe
yes it is to cold today to swim
no
8.0
learn to swim
no it cold
SWIM!