Short Riddles and Answers

Question: Whats a question that gets asked a lot and has many different answers to it.

Question: What are the next two letters in the following series and why? WATNTLITFS__

Question: It is always bought when you're hungry, but it doesn't get eaten. What am I?

Question: What is often picked but seldom chosen, never walks but can run when frozen?

Question: I have lakes with no fish.
I have roads with no cars.

What am I?