Why is driving in snow at night dangerous?

I’m thinking about buying a used Volvo. I’m aware of what’s included in their CPO warranty, but I can’t figure out what’s not included. What is excluded from Volvo’s CPO warranty?

My family is coming to New York City from Portugal, and we’re planning to rent a car. We’re going to tour a few states, but I’m not sure about international driving permit requirements. What states require an IDP?

I’m getting ready to go on a road trip through Tennessee and I’m a little nervous to take my car on all of the hills. How do you drive an automatic on a steep incline? Should I put it in a different gear to make sure I make it up the hill?