Here are five exercises related to set theory:

1. Basic Set Operations
   Let $A = \{1, 2, 3, 4\}$, $B = \{3, 4, 5, 6\}$, and $C = \{1, 5, 6, 7\}$.
   Find:

   • $A \cup B$ (union of $A$ and $B$)
   • $A \cap B$ (intersection of $A$ and $B$)
   • $A - B$ (difference between $A$ and $B$)
   • $A \cap (B \cup C)$

2. Subset Verification
   Given $X = \{1, 2, 3, 4, 5, 6\}$ and $Y = \{2, 4, 6\}$, determine if:

   • $Y \subseteq X$ (Is $Y$ a subset of $X$?)
   • $X \subset Y$ (Is $X$ a subset of $Y$?)

3. Power Set
   Find the power set of $P = \{a, b\}$.
   (Hint: The power set is the