Re: 1. I don't think it's a set temp as much as a difference from the daytime temps. So for us average Americans, 15-19C (59 to 66F) would probably work well,

Re: 1. I don't think it's a set temp as much as a difference from the daytime temps. So for us average Americans, 15-19C (59 to 66F) would probably work well, depending on where you live in America.