Let $A = \{1, 4, 9\}$ and $B = \{1, 3, 6, 10\}\text{.}$ Find each of the following sets.

1. $A \cup B\text{.}$
2. $A \cap B\text{.}$
3. $A \setminus B\text{.}$
4. $B \setminus A\text{.}$

Your answers should include the curly braces