They are a special towel that has to be wet to absorb water (when they are completely dry they feel like cardboard). basically they just help to get rid of any excess water on your body.
To proect their bones from breaking
Divers go in the spa so they don't get cold after each dive.
Its where their batteries go.
20 or just under
The small pool is a hot tub; divers go in to keep their muscles loose.