so discouraging.

#help

What groups do the other two or's belong to?

The whole explanation of subsets and supersets and circles with the dots really helped me to grasp the concept of the sufficient vs., necessary. Then to expand upon this further to the notation was really helpful.

I may have missed the section on blind review- how are we supposed to know the right/wrong answer before we click to the answer?

#feedback. The player on this will not allow me to change the speed.

#feedback - I think this should be in the first lessons, before the foundations set - so we can be doing this from the very beginning.