There are two reason, and you will need both to really answer your question.

It is no longer certain whether they need to answer any of them.

That can be our business if we need to answer questions.

But you need to answer a couple of questions first.

The player in first place needed to answer 4 questions.

Have I left out anything that you need to answer your question?

You do not need to answer any of the other questions.

There were so many questions she needed him to answer.

These are the two questions which we need to answer.

We actually need to answer some key questions to be able to do this.