TASK DEFINITION: You are given a sentence from a conversation between a human and a virtual assistant. Your task is to identify whether the sentence is a question or not. Answer with Yes or No.
PROBLEM: Yes. What's their phone number?

SOLUTION: Yes

PROBLEM: Nah, that will do for now.

SOLUTION: No

PROBLEM: Please confirm you would like me to book a reservation at Anar in San Francisco at 12pm for 3 people.

SOLUTION:
No