Hello how may I help you? Hi, I have a question about time zones. Sure, what would you like to know about time zones? How many time zones are there in the United States? There are three different time zones in the US. Oh, what are their names? The three time zones Are PST, CST, and EST. Would you like to know what they stand for? Yes, please. Pacific Standard Time, Central Standard Time, and Eastern Standard Time. Which time zone is Nashville, Tennessee in? Nashville, Tennessee is in CST.