Definition: For two sets A and B the symmetric difference of the sets A and B is denoted by
$A \triangle B$ and defined by: $A \triangle B = (A \cap B) \cup (B \cap \overline{A})$.
Suppose A, B, and C are sets. Carefully prove the statement: “$C \subseteq A \triangle B$ if and only if
$C \cap (A \cap B) = \phi$ and $C \subseteq A \cup B$.”