Misc: In the 9th century which city had several thousand bookstores?

Questions

What is added to the ice & water mixture in domestic ice cream makers in order to lower the temperature?

What is the only state with an official state ship & hero?

What mountains are located on the border of Tennessee & North Carolina?

What one word makes sense when it precedes top, drive & rock?

What was the name of the first US communications satellite to amplify radio & tv signals?