A person from the company where I'm working send me an email telling that we are meeting on the 3rd floor, but she forgot to mention the name of the room where we are meeting, so I want to ask her about that. How can I do it properly?
Ways that come to my mind:
1: Which room are we meeting at?
2: Which room are we meeting in?
3: In which room are we meeting? (is this even gramatically correct?)
4: What's the room where we are meeting at/in)?
5: What's the name of room where we are meeting at/in)?