The conversation between human and AI assistant.
Why do some US interstate highway numbered exits have letters after them (Ex: Exit 54B)?
Ah, I see. So it's kind of like a subcategory of the exit number?
Exactly! It's just a way of providing a little more detail about the exit. For example, if there are two exits on the same highway that both say "Exit 54," you would look for the letter to know which one to take.