During the commitment phase all you need to do is commit to using the site when it goes to beta. The sample questions for the site have already been asked (and sometimes answered) during the previous phase. Those served to define the content of the site. During the commitment phase, samples are no longer needed. All that's needed now are people.
The questions you're expected to ask and answer in your commitment are for when the site goes to beta and becomes a regular Stack Exchange Q&A site. If you've committed to the site, you'll be notified by email when it opens for beta. At that point, feel free to re-ask your sample questions (the on-topic ones, as well as maybe the occasional off-topic one... after all, what's a beta without testing the negatives as well?) as well as any new ones you can think of.
The sample questions during the definition phase of the site on Area 51 aren't really meant to be answered. They're just examples of the questions that are to be expected on the proposed site. But once it's in beta, it should behave as a full Q&A site and, hopefully, you should be able to ask questions and get good answers.