Correction of list of videos for Part 4.4
I have corrected an error in the list of videos for Part 4.4.
There are now two videos listed where previously there was one. Previously the link connected to the Venn diagram video if you clicked the link on the left, and the "picking a committee" video if you clicked the YouTube button. That has been fixed so that both videos are available in the left column as well as at YouTube.
