Please before biding check Joomla Comunity ANswers plugin! It's have already option to send notification emails so I just need to modify what information is sent.
What need to modify when notifications are sent to subscriber email I need to include answer to it and name who answered . Because currently people receiving only notification that your question is answered in the body and link where you can click to get to the website and read answer . So there need to add extra content what was answered . The reason why need it it's many people using emails on the phone so instead every time going to website check the answer they can receive it on the phone so they don't need every time go to the website and spend lot of time until pages will load .
Bid only if you can start work on it right away and finish today . I know that good developer can fix it in few hours since it's just addon to the existing emails .