Can answers be limited to a privileged group?

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I want to create and askbot site with the following setup:

• Free registration, everybody can open an account.
• Everybody can ask a question and comment on a certain question.
• Only a certain "expert" group can reply an answer to a questions.
• (optional) everybody can vote up/down answers.
• There might be an intermediate "moderators" group with permissions to tag, edit, etc.

Is this setup supported?

Thanks!