somewhere top right of the page should be a panel saying 'Got an answer?' or something like that. If you click on that, it will stop you getting any more emails saying 'You have an answer'. It won't remove the question - which stays in the archive so other people with the same question can read it (not that anyone does...) - and it won't stop anyone posting an answer, but at least it saves you being woken in the middle of the night by bells ringing to announce that another email has landed