# Hasse diagram vs digraph and bounds question

I have attached a link to my hasse diagram I drew... Sorry about image size and rotation.

So is it correct to say a hasse diagram is just a digraph with each internal vertice removed? So would my diagram A be a digraph not a hasse diagram? The book gave us a hasse diagram which I copied under B there which has a intersecting vertice so that got my confused. How can I make my diagram in A work?

My second question is about the bounds of a hasse diagram that I'm not sure about. For B.

  1) What are the upper bounds for {d,e,c} My guess is b? Not sure about this one.
2) What are the lower bounds for {c, b} My guess is d? Since its the farthest down connected by both
3) What is the least upper bound for {f, c}. My guess is e? Since its in the middle but I'm not sure if its a lower bound or upper.

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