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Definition: The power set of a set \(A\) is the set of all subsets of \(A\). The power set of \(A\) is written \(\mathcal{P}(A).\)

For example, let \(A = \{a, b, c\}\). The power set of \(A\) is \[\mathcal{P}(A) = \{\emptyset, \{a\}, \{b\}, \{c\}, \{a, b\}, \{a, c\}, \{b, c\}, \{a, b, c\}\}\] Notice that the power set is a set of sets. So, while \(\{a\} \in \mathcal{P}(A)\), \(a \not\in \mathcal{P}(A)\) since \(a\) is not a set. Also, notice that \(\emptyset \in \mathcal{P}(A)\) and \(A \in \mathcal{P}(A)\). The empty set belongs to every power set, and every set belongs to its own power set.

Only enter numbers from 1 to 3.
\(\mathcal{P}(\)A\()=\){\(\emptyset\), {1}}
\(A\) is not a set. \(B\) is not a set.
Choose all the sets in \(\mathcal{P}(\{a, b, c\}).\)