Nope.
No, the lower deck is fully enclosed with windows that open up, but no air conditioning.
Possibly, but the windows and doors are open for people to view the scenery. On hot days I would say they would, but again I can see them not doing that.. I know it doesn't help, but how it's situated, I also want to say no. When I went, it was hot but tolerable, and they did not have it on downstairs.
We went in early fall and we had extra clothing. It's usually cooler at fall time.
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