The expression that represents Ms. Parparian's situation is:

$22 - 5$

This is because she starts with $22 and then spends $5 on lunch, so you subtract the $5 from her total.

Would you like any further details or explanations?

Here are 5 related questions to expand on this concept:

1. What is the result of the expression $22 - 5$?
2. If Ms. Parparian buys something else for $7, what will the new expression be?
3. How much money will she have left if she spends another $10 after lunch?
4. What if she finds $8 after paying for lunch? How would you write that expression?
5. How would the expression change if she started with $30 instead of $22?

Tip: Subtraction in math often represents spending or losing something from a starting amount!