Statistics behind field of vision: (lecture)

This is an edited lecture. I removed parts when we had difficulty with the streaming and also removed the final part of questions as there was a hacker with inappropriate works written on screen.

To Avoid such problem, next meeting will be on YouTube live only. This means questions can only be submitted in written way. But the advantage is clear .... saving time, no interruptions and no hackers
Also I believe the voice will be clearer.

(lecture)