Instruction: Evaluate the answerability of a question by analyzing the related document, outputting yes if the document contains information addressing the question, and no otherwise.

Input:
Question: How many keys come with each lock?
Document: This is a high grade lock that works on the new CBUs. they are well made and have no defects.
This product works great with the type of mail boxes that I work with. The only problem was there was one piece not included with this lock but it still worked out fine.
The order was shipped and received as promised. The locks work as expected. We have ordered these several times and each time the service was excellent and the locks meet expectation. We have a large townhome complex and are forced to change the locks more frequently than the want.
Answer: no