Give the elements of the partially ordered set, which covering relation is:
$\{(A,B) \in \mathcal{P}(\{a,b,c\})^2:((A=B \cup \{a\})) \vee(A = B \cup \{b\})) \wedge(A \ne B)\} $
I have some difficulties with this $\mathcal{P}(\{a,b,c\})^2$ part I know that $\mathcal{P}(\{a,b,c\}) = \{ \emptyset, \{{ a\},\{ b\},\{ c\},\{ a,b\},\{ a,c\},\{ b,c\},\{ a,b,c \} }$
Also the meaning of the second part $((A=B \cup \{a\})) \vee(A = B \cup \{b\})) \wedge(A \ne B)\}$ is pretty ununderstandable for me. Should I maybe draw a Hasse diagram?