This video, https://www.youtube.com/watch?v=T6XpXCLPHuA&list=PL-BrKY3INkw1gHZbX0J6ztwrCBTrX1jlM&index=4, can also be seen at https://www.youtube.com/playlist?list=PL-BrKY3INkw1gHZbX0J6ztwrCBTrX1jlM.