I did ask,Hugh,and that was fascinating,you gave a good delivery of the science aspect, it was only ruined when you peppered it throughout with sarcasm directed at me. If there was a pupil in a class taught by someone like you,they would have learnt nothing,the reason being you was to smug in making quick judgements on peoples mental health,in which you are not really qualified. Once you insult someone you have lost their interest. So work on your people skills.