"A fair question is, Which ones and where are they?"

Certainly a fair question based on what he had seen of my writing.

I don't really know the answer though it seems a fair question.

It is a fair question, and allows of more than one answer.

Those are fair questions, and I hear them a lot.

A fair question, but one I have no way of answering.

A fair question, but I do not know the answer.

A fair question, which didn't get much of an answer.

It's a fair question: where do you go from here?

Those were fair questions, for which Jim had no answer.